I could make endless posts about how I wish we knew just anything about Adrian's childhood (aside from that he has a brother and his father is gay) because I think that would lend itself to better characterisation but for now, I'll just make a near-baseless headcannon.
this stems from the idea that he resents her for how he was treated by gut, his lack of knowing how to treat his loved ones, and probably his father leaving, too.
not proofread :0
firstly, lets discuss Adrian's relationship with gut chase. gut is his older brother that was originally chris' friend and is an original character for the peacemaker show. as far as we know, gut is alive and that him and Chris were relatively close, meaning he's likely around chris' age at 40. in ep8 s2, we find out that "[gut] really wasn't good to him" and that's pretty much all we know.
from this, I have inferred that gut was abusive, in some degree, to Adrian and he's grown resentful of his mom for not protecting him. I think this mostly for the fact that his mother coddles him so much. she lets this 30 something year old man live in her house without pestering him to move out and even plays so much dnd with him that she's a lvl 40 thief and she's letting him talk to her like that. whether this is because she's always been so non confrontational and just wants her son happy or because she feels bad for allowing gut (who is 9 ish years older than Adrian) to fuck around with him like he did I don't know, you read into what you like.
this idea that gut was abusive to Adrian works in conjunction with his and chris' relationship. seeing as Adrian likely never really had a good older brother figure in his life (or father figure), I imagine that he latched onto chris as something adjacent to that. whether because chris was not as cruel to him or because he was sort of the only choice, again, I don't know but knowing (inferring) how gut treated him and then going to chris who is on a less extreme side of that spectrum makes more sense why Adrian puts up with effectively being used for chris' own issues.
in constantly needing reassurance that someone likes him and he is wanted, chris unintentionally (probably) creates this dynamic with Adrian where they can both get what they want off each other. chris doesn't need to confront his own issues and self worth so long as Adrian is longing for that positive older brother figure in his life that can be manipulated (see adebayo).
I don't know if James gunn has ever thought at least a little deeply about Adrian's character so that probably wasn't intentional, but I think this interpretation works narratively better than just making Adrian sort of obsessed with chris because his brother was a little mean to him.
a sub point to this I suppose is also that his relationships with his loved ones (chris, his mom, gut, his father) are like quite shit. we know that he struggles particularly with understanding social cues and really I guess normal dynamics with people and, as a byproduct, his treatment of his mom is representative of how he doesn't have those 'normal' relationships with his loved ones.
whether he has aspd or autism, they both share relatively common symptoms that could explain him not being sensitive or respectful of others, aggression (aspd symptoms) or social communication and interaction issues and unusual emotional reactions (asd symptoms). despite these symptoms, people with these disorders are still able to form relationships that don't look like Adrian and his mom, so im assuming he (in conjunction with these symptoms) was just never really shown a good enough role model to give him some guidance on forming these relationships.
from the way gut, his older brother who was supposed to love and care for him, treats him to chris, his supposed best friend who lets him believe that his father is only gay to get away from him, Adrian has no proper role model. speaking of, I think his father not being around also acts as another factor of why he's seemingly unable to form and understand when relationships aren't healthy, because he hasn't seen a healthy relationship specifically in his parents probably ever.
I will say, his unusual emotional reaction to his father not being gay in earth x speaks to the fact that he probably doesn't overly care about his father so I won't focus much on him outside of the fact that Adrian's resentment could also come from his father leaving. im not 100% into this because there just isn't much evidence at al, but it could very much just be like a hidden thing he's largely not come to terms with yet (BECAUSE HE'S GAY) but I don't want to rule it out entirely.
all of this is to say that Adrian's treatment of his mother likely stems from some internalised issues made worse by how gut and chris have been treating him. I think he has the potential to be such an interesting character but was used just as like comedic foil for chris and the general seriousness of the show.
or I mean he could just be a dick idk. treat your mothers well, folks (unless they don't deserve it)