Life of Mental/Physical Abuse:

They both had mentally abusive upbringings which is obvious to say has a huge effect on your development and how you perceive the world around you. Theon was the youngest of 4, known to cling more to his mother and not care as much about the ironborn mentality of piracy and raiding as his older brothers did. He was constantly tormented and bullied by them for it as well as feeling neglected by his father for “showing weakness” which made him feel like he didn’t belong and wasn’t accepted in his home. He was then sent off to be Ned Stark’s ward (prisoner) and would be executed if Balon tried to rebel against the throne again. This knowledge is constantly hanging over his head and threatening him even though he makes the best of the situation, especially by finding a brother in Robb. The North and most of the Stark family don’t accept him despite his best efforts in trying to do his best while also missing the Iron Islands and not being able to fulfill his right as the heir to the salt throne

Ben has been mentally abused since he was in his mother’s womb. Palpatine has been in his head since he was conceived, trying to seduce him to the dark because he knew the power Ben would possess from his family. Now were his parents abusive towards him like Balon, Maron, and Rodrik were to Theon? No. But they were afraid of who he could become which definitely drove him towards becoming what they were afraid of to begin with. He felt isolated and alone. Aside from questioning why his parents were afraid of him with no explanation (making him feel like he was some sort of monster), Han was gone the majority of his upbringing and Leia was building the New Republic. He was often left with droids to watch him, further developing his isolation. There’s also apparently an instance where a droid fantasized about killing him and how they’d be able to cover it up? Eventually, L&H sent him off to be trained by Luke due to their growing fear of him becoming like Vader, but he didn’t know because they never told him Vader was his grandfather. He ended up finding out later on when it was announced at a senate meeting that was broadcasted on the holonet. (Keep in mind he’s consistently being mentally tormented and tempted by the dark but fighting it off)

Loss of Identity:

I think you can argue that Theon and Ben have struggled with their identity their entire lives. Before Theon was taken to Winterfell he already felt like he didn’t belong. Then he does his duty as Ned’s ward, placing him in the midst of the rest of the Starks and trying to figure out his place without stepping out of line but also wanting to fit in as best as he can. After Ned dies and he’s at war with Robb he is able to return home to persuade Balon in lending his fleet to help Robb. Balon refuses and now Theon is stuck in deciding if he should help Robb or win over his father and take back his place as a Greyjoy. He leads an attack at Winterfell, betraying his loyalty to Robb, killing two farm boys that all of Westeros believes is Brand and Rickon, which leads to him getting overthrown by the Boltons taking Winterfell back, putting him in the hands of Ramsay who tortures him mentally, physically, and spiritually to the point where he takes on the persona of Reek and truly believes that’s who he is, who he was meant to be and who he deserves to be

Ben has also had this lifelong struggle. He’s tried to follow what his parents have taught him while fighting everything going on in his head. He looked up to his dad and wanted to be a pilot like him despite Han being gone a majority of the time. Not to mention just the pressure he faced with being Han & Leia’s son as well as Luke Skywalker’s nephew. But he could sense and sometimes hear his parents discuss their fear of who he is/who he will be. He was under the impression that they thought he was or could become some sort of monster and gave him no explanation on why they would think that and then was sent off to train with Luke (when there’s no real indication that he wanted that, he just voiced how he wanted to be a pilot) Luke could sense the same darkness in him as H&L but instead of helping him and having a conversation about it he decided to sneak into Ben’s tent one night and kill him before his fears came true. Ben awoke to his own uncle standing over him with an ignited lightsaber about to strike him down. Yes, Luke regretted it the minute he ignited it but it was too late, Ben was awake and betrayed. What he didn’t do (but the galaxy thought he did) was destroy the Jedi temple and the rest of the padawans, a higher power (most likely Palpatine) did and Ben was upset about it and he didn’t want them all to die. He felt like he had nowhere else to go and succumbed to the voice that had been tormenting him for 23 years (but in a way was the only consistent thing in his life) and went to Snoke. He felt unwanted, untrusted, and doomed to become this awful being everyone around him thought he would. He took on the persona Kylo Ren and allowed Snoke to continue to torture him mentally and now physically and spiritually to ultimately turn him into Snoke's chess piece to take over the galaxy

Path of bad decisions driven by the need to please their abuser who gives false hope of a home:

Parts of this are redundant but they both have made some terrible decisions that were heavily influenced by the manipulation of their abusers and a need for a sense of acceptance and belonging. Theon wanted to please Balon and later Ramsay, Kylo wanted to please Snoke and his grandfather (who we later find out was all Palpatine). The majority of deaths that Kylo is blamed for were under Snoke’s orders and Kylo was either unaware they were happening or tried to prevent them and resort to other solutions to get whatever it is they wanted. He killed his father because he was convinced it would make him stronger and reach his potential on “who he’s destined to be” when really it tore him apart and destroyed him, 

similarly to how Theon felt after he killed those farm boys and saw what his actions had created for Winterfell and Westeros 

Acceptance of “who they truly are” through self-hatred and regret:

Through this they come to terms with their actions and the destruction that has followed from those actions. They believe they deserve the pain and suffering they’ve had their whole lives. Theon is constantly saying how Theon is dead, he’s Reek and he deserves to be. Ben states how Ben is dead, he’s only Kylo now and that he deserves to be seen as a monster.  

Needing help to be pulled back to their true selves:

Their inner conflict is clear through both of their journeys and it’s clear that others can see that. They need help to be pulled in the right direction and reminded that they’re not the person they think they are. Yara comes for Theon when everyone else has given up on him. He’s her brother and regardless of what he’s done she still cares for him and believes in him. However, even the love of his sister can’t persuade him or break the abusive turmoil he’s been suffering and he stays with Ramsay as Reek. 

Then Sansa comes, someone he has grown up with and cares for. She learns the truth that he didn’t kill Bran and Rickon. She knows who Theon really is and she brings him back, she needs him back and gives him the strength to do it. 

Similarly, we see Han trying to bring Ben back in TFA, and like with Yara and Theon, it doesn’t work. He believes Ben is dead, that his family gave up on him and he did too so he can only be Kylo now. And as we see later on, the act of killing Han only made it worse and caused a deeper pain and regret to Ben as well as the conflict on where he lies in the force. In TLJ we see this and how Kylo seems to be chipping away from coming to terms with everything he’s done. 

(I would also like to point out that in TLJ Ben couldn’t kill his mother and it’s stated that had he noticed quick enough he would’ve stopped the blasters from hitting the bridge) He gets a connection with Rey, who at first wants nothing to do with him and sees him as the monster he thinks he is. But similarly to Sansa, she finds out the story Luke told her about him destroying the Jedi Temple was a lie and from then on they’re able to console in one another and understand the pain and isolation they’ve both felt their whole lives. 

When Luke refuses to go back and help Rey and the resistance she takes it upon herself to go and fight to bring Ben back to the light because she can see that he’s still there.

Taking a stand against their abusers, specifically to help save someone they love:

They both go against their abusers and take a huge leap towards taking back their true selves. Theon wants to help Sansa and she gives him a few chances too, for example with the candle but he ends up telling Ramsay. However when Ramsay is gone Sansa is crossed by Miranda and even though he’s still filled with fear and conflict, he throws Miranda off the ledge to save Sansa and finally defies his tormentor and everything that he’s done.

Kylo retrieves Rey when she lands on the capital ship and takes her to see Snoke. In the elevator they both state how they’ve had a vision of seeing them by each other’s sides. Kylo takes it as Rey joining him in the dark but Rey sees it as him reclaiming who he was supposed to be and even refers to him as Ben which he responds to. 

(for the majority of knowing him she called him Kylo, monster, etc but since they touched hands and she saw the conflict she now sees him as a real person and more importantly Ben) Snoke wants Kylo to kill her in order to reach is full potential since killing Han only made him question the path he was going down even more. However, he tricks Snoke and instead kills him instead of Rey, destroying his abuser and saving Rey who is the only one he’s ever been able to connect to.

Reclaiming their identity:

Even though they have someone in their corner, believing in them and helping them to come back to who they are, it takes time. Theon stays with Sansa until they cross paths with Brienne and Podrick and knows she’ll be safe with them. He then heads back to the Iron Islands to join Yara and help her however he can. He still feels as though he’s Reek and doesn’t deserve any redemption or to be trusted/loved. 

Overtime those who still believe in him and given time to heal he reclaims himself as Theon Greyjoy, not even the one from before, but a better and stronger man because it’s who he chooses and wants to be. He saves Yara from Euron and goes back to Winterfell to help fight against the dead. He protects Bran at the Weirwood tree bringing it back and trying to rewrite his wrong when he took Winterfell from Bran and caused him to abandon his home. Even though Arya is the one to ultimately save Bran by killing the Night King, she wouldn’t have been able to without Theon and his sacrifice.

Now Kylo’s is a little different and his journey back to Ben takes a few more steps. Killing Snoke was supposed to be him reclaiming himself and finally getting rid of the demons that have been haunting him his entire life. But now we’re aware that Palpatine created Snoke and was the one who has been in his head the whole time so really those voices are still there, abusing and tormenting him to do what they want. Except now he has something more to fight for. He knows Rey believes in him and they have a bond, a force dyad, that hasn’t been seen for centuries. We don’t get to see much of how Supreme Leader Kylo Ren deals with First Order affairs but I would assume it would be different from how Snoke handled it considering (as stated earlier) Kylo tried to get what they needed in the easiest way, preventing as much unnecessary harm or death. (I also would like to point out that at the beginning of TROS we see Kylo in Mustafar and all of the people he’s killing are Vader cultists so they were bad beings) He then travels to Palpatine who reveals it’s been him all along in his head and Kylo threatens to kill him, but then palp shows his army he’s been creating, how it could be Kylo’s, and reveals who Rey truly is. Palp wants him to kill her and he tricks him into thinking he will when really he chases her around to tell her this information as well as see if it’s true and to prevent her from getting killed. They fight a lot but it’s always Rey initiating it and Ben defending himself when he needs to. He gets distracted during one of their fights because Leia is reaching out to him and in the process, Rey stabs him with his own lightsaber (death of Kylo Ren) but ends up healing him and tells him that she did want him, the real him

He then has a vision of Han and basically reenacts what happened in TFA but has it play out how he wished it did the first time. He is now truly Ben Solo and goes to Exogal to help Rey and defeat Palpatine. After Rey kills Palpatine she dies and Ben comes back (he was thrown down deep pit) and transfers his life force to her to save her. Like the situation with Theon, if Ben wasn’t there Rey wouldn’t have been able to defeat Palpatine and save the galaxy.

Only got to live in peace with themselves for like 2 minutes:

They both get complex, intriguing, and beautiful arcs of redemption that represent realistic struggles of life and grey morality that people face throughout their lives. But they both end with a terrible message that the only way to fully redeem yourself from past mistakes, bad decisions (even if it was influenced by a life of mental/physical abuse) is to sacrifice yourself.

Theon sacrificed himself to save Bran and the fate of Westeros and was only able to be at peace with himself for about the last 20 seconds of his life because Bran forgave him, told him he was a good man and confirmed the type of person Theon really is and always wanted to be.

he deserved to feel this way for a MUCH longer time and continue to heal and grow and live a life that gave him much more peace and happiness (preferably with Sansa 😏) but instead he only gets to feel good about himself for the first time in his life and have it only last for a moment.

Once Rey defeated Palpatine it’s safe to say that the voices stopped in Ben’s head. There’s no more tormenting, persuading, or taunting. He climbs out of the pit to find Rey dead (his literal other half) and channels the rest of his energy to bring her back and it works. Similar to Bran, Rey confirms her joy and acceptance of Ben being back 

and he would’ve been fully content with that, but Rey kisses him and he smiles for the first fucking time we’ve ever seen. His mind is at peace, Rey is alive in his arms and for the first time he is truly happy. And then he DIES. 

Who knows what would’ve happened to him and how the resistance would’ve reacted, but he deserved the opportunity to atone for the mistakes he made, live life with a clear mind, as well as continue to be the other half of Rey that brought balance to the force and galaxy.

Bonus:

They both deserve to be with the only person that fully understands them and their pain and can grow, heal, and live in peace together.