Oh god this is everything I ever wanted bless you <3
I’d like to add/point out the small detail (not necessary, but I always get ASKJDHASLKD when I think about it as plot point) that Aaron’s mother turned abusive toward him only after Andrew came into the picture. Andrew, in Aaron’s backstory but also the present of the book, is both the poison and the cure at the same time, and I think that a lot of Aaron’s conflict with his brother comes from the fact that cause&effect are mixed up, and Aaron’s stuck in a loop (Andrew saved him from his mother, but he needed saving only because Andrew showed that he existed, but Aaron wanted to meet him so much so maybe it’s his own fault but he couldn’t have known and things could have gone differently, maybe it’s his mother’s fault and his own fault and Andrew’s fault). All this without even touching how much knowing about Drake and Andrew’s reasoning behind his actions complicated the picture.
Another thing that I find interesting about them is that I don’t think Aaron was all that passive in accepting Andrew’s deal and then letting him “control” his life. First thing, Andrew is too obsessed with consent with his closed ones, I can’t see him overstepping his bounds. He’s always been clear with Aaron, and has always given him the chance to back off. Aaron is the one who didn’t take seriously their deal. Second thing, Andrew offered Aaron to keep their deal after high school once they graduated, and Aaron accepted.
So yes, I think that Aaron deeply needs someone to love him, and he can’t shake off that undeniable pull he felt the first time he found out about Andrew (back to the last paragraph, the added conflict of what he thought of his mother for doing something like that, assuming that Tilda wasn’t doing such a disastrous job as a mother till then), to the point that even after everything, even when he’s fighting between numbness and hate, he can’t, won’t, and doesn’t want to leave his brother’s side.
The depth and complexity of his feelings (and his character in general) toward his brother are incredible, and chapeau to Nora for giving us all the hints to connect the dots even through Neil’s incredibly biased point of view.
P.S. Added bonus to his complexity as a character: he’s known for his homophobic lines, but I don’t recall Nicky ever showing being uncomfortable around him (please correct me if I’m wrong, I’m working with memory). Even with Nicky’s past, both the one with his parents and the assault at Eden’s, he never stopped being himself in front of Aaron, never acted as though he felt targeted or rejected or a stranger in the family (if anything, I think both Nicky and Aaron have very similar views on how important Family is). This not to excuse his attitude, far from it, just to understand him. Nora has confirmed that his homophobia is a learned behaviour, and through the books we also see that it’s confined in the realm of words (he never acts against Nicky and Andrew for being gay; I don’t recall him agreeing with Nicky’s parents in TRK but I might be missing his parts?) (I can accept the reply that instigating Andrew to attack Nicky for the rape joke is an indirect act, but considering that situation I don’t know who was more in the wrong; plus I have an inkling that his focus was on pushing their buttons, not making a point against Nicky’s sexuality). It’s possible that Nicky knows that his homophobia is a habit - which can be unlearned - through copious exposition if you ask Nicky - and that he’s not a danger.