I feel like, within our modern day political framework, if you have a parent who's a homophobe or a transphobe, there's just enough people saying "no that's wrong" that it allows you to step back and begin to clearly see other ways in which they're unfair against you.
but if you're not trans or queer or your parents aren't that flavor of bigoted, but they are horribly ableist, that's a million times harder to clearly see. because ableism isn't really... something that's visibly discussed in the mainstream discourse? there's no one who's not simply ridiculed out of hand saying things like "it's unfair to expect your autistic ADHD child to be able to function completely independently". it's simply taken as a baseline fact by almost all of society that everyone needs to be held by the same standards of productivity and independence, and even the few exceptions are seen as pitiable and pushed to the margins. so you have nothing except your friends' words (and that's if you're lucky) working against this life-encompassing narrative of all your shortcomings, the ones you can't seem to overcome no matter what you try, actually being your fault. and that's a hell of a lot harder of a mental hole to crawl yourself out of.