#jetfire mentioned

If one of them was upset, the other would get flowers that signified their love. Starscream got lavender, Pax got carnations. Plants are rare in Cybertron, so the effort was more special.

When Orion Pax quit due to these mounting concerns and disagreements with the Council, Starscream was enraged. How could he leave when the answer to what the Matrix really does is within their grasp? When everyone, except Jetfire, ridiculed his skills and dreams? (Unfortunately, Screamer projected his relationship issues onto Jetfire, leading him on mostly unintentionally and pretending the white bot could be like Prime.)

For a short period, Orion Pax joined a team of warriors hoping to overthrow their hostile government. Megatron was the leader. You can probably see where this is going. The two split into the Autobots and Decepticons after the warlord's methods proved to be more ruthless than their foes. (He gets visibly pissed when Megatron slaps Starscream presently. Physical abuse follows Starscream like a hawk. His superiors at the lab hit him too. Prime just wants to protect him, but his ex-lover hates him for it.)

Optimus Prime, no longer Orion Pax, emerged when the Matrix attached itself to him. His ex-lover wept in private. Dedication gets you nothing. Caring gets you nowhere. You are worthless. Even the subject of your fascination/purpose has rejected you. (Starscream did not go to Prime about any of these wounds, so he's still ignorant about why the jet looks at his chest, where the Matrix resides, with revulsion.)

Starscream joined the evil faction partly to spit on Optimus and partly to prove his worth. He doesn't like fading into the background.

Being trapped in this digital reality centuries later was one of the best things to happen to the jet. He learned coding by studying each environment's inner layers. Hacking challenges and transporting himself to places he shouldn't be allowed to go. Preparing for the ultimate battle where Optimus Prime could finally be humiliated. As well as his lackey friends.

That didn't work out. So, Starscream continues to play the 'king' role while also trying not to be too disturbed with how easily his captors control him. Prime sees his mental struggles but forces himself to stay away. They hurt each other too deeply when they come into contact.

Optimus does want to free everyone from this digital prison, including Starscream. He finds the constant fights exhausting and depressing. They aren't allowed quiet moments. Friends turn on each other for power. He regularly asks every bot he encounters the question," What do you want to do?" Trying his best to fulfill their wishes. Fighting isn't the typical answer. For Starscream, it is. That's what he'll have you believe anyway.