Here's the thing about being unloved by a parent: You don't receive the proper lessons on how to love yourself.
We don't know how old Robby was when his mother abandoned him but we can infer by the way he speaks of it that he was old enough to remember. He was either dumped at his grandmother's, or the state got involved when he was abandoned and he was placed with her.
The thing about childhood development is that we learn so much from our first interactions with our parents. There's a saying that you don't really become "people" until you turn five because that's when a child really begins to gain consciousness of the world around them. But in terms of SEL (Social Emotional Learning), those lessons begin very early.
If his mother couldn't be bothered to love him the way she should have, then Robby never learned that he should love himself. His grandmother, however, most likely taught him to love others, even through loving him. We've seen his capacity to love others. He's compassionate, empathetic, and deeply caring. It's like if you spent your early formative years with a parent who called you ugly and then as you aged you lived with someone who saw beauty, you would learn to see beauty as well. But not in yourself. It doesn't matter how often someone tells you that you're beautiful, you are unable to believe them, but as soon as someone tries to say that another person isn't, you can cut in and correct it. This is the same thing. Objectively, Robby knows love. Subjectively, it's foreign to him.
His SEL has been stunted by a mother who abandoned him. Judging by the percentages of mothers who abandon their children, chances are that while in her care, she neglected him as well.
All of this culminates into an adult with a capacity to love and care for other people, but not for himself.
If his mother rejected him, there must be something fundamentally wrong with him, right? At least that's what he is thinking.
Never mind that his father isn't mentioned at all. He's obviously not in the picture, otherwise Robby would have gone to him and not his grandmother. Now we have two parents that have rejected and abandoned him.
Keep in mind his empathy for Baby Jane Doe -- an infant also rejected by her mother.
Robby needs to feel useful in order to feel like he can be deserving of kindness and grace. Which could be another symptom of his mother abandoning him and/or the time he did spend with her prior. She may have demanded things from him. Potentially only showed kindness or gave praise when he was useful to her.
That's another lesson learned.
Unfortunately, by the time he gets to his grandmother, these things are ingrained. I've been using C-PTSD to describe a lot of his symptoms, and I've received a little pushback for that, but I'm holding my ground with this. Especially with the new information we have. This is childhood trauma, and it deeply shapes a person's mental health and their life experience.
Robby can't love himself but he knows what it is. He's begging without saying for someone to love him. He needs to feel useful to feel deserving. If he does decide to end it all, maybe if he leaves the ED a little better, then someone will look upon his portrait with the same love he looks upon Adamson's. If he can be useful, then maybe someone will finally love him. But Dana told him in 2x12 that he wasn't needed. She didn't mean it like that, but to a mentally ill person, it's going to be read in the worst way possible. And all Robby wanted was reassurance that he's useful and thus loved.
The thing is, he is loved. But he's been so damaged by his mother that he can't see it. Knowing how to love and knowing how to be loved are two completely separate things.
These types of parental injuries, these wounds will fester over time. And the worst part is the child-then-adult often doesn't have the lived experience to know and parse through the mud to figure it out. This is normal to them. And normal doesn't need fixing.