This site is quite strange in that there is a clear (and not obvious) prioritisation by age and sex.
First comes teenage girls and young women, up to about 22, whose feelings, according to some posters, should always be prioritised, and their behaviour tolerated-because hormones (I think).
Then comes actual children, with girls first. Amazing how many posters sympathise with women disappointed that they are having a boy, as off that is somehow second best.
Then teenage boys, adult women, and finally adult men, whose feelings are generally minimised and behaviour labelled abuse on the flimsiest of evidence (not saying there aren’t plenty of abusive men btw).
The worst I saw was the advice to a mother who was sleepless as her teenage daughter (who had quit education at 17) talked loudly on the phone to her boyfriend all night. She was advised to buy earplugs! The other one is that teenagers’ rooms are sacrosanct, so they can leave them with rotting food, stinky clothes, but must never be entered.
A lot of the pandering to teenagers is a total symptom of privilege and being spoiled. If you didn’t have plenty of money, you couldn’t trash a room or abandon education to be up all night talking to a partner. You couldn’t witter on about your feelings whilst enjoying an expensive university education and using your family home as a hotel (although you wouldn’t treat hotel staff like this girl is treating your mother). The idea that any of these lack of boundaries is good for teenagers is plain wrong according to any educational or psychological theory, but somehow it passes for good parenting on this site,
In this case, I sympathise a little with the daughter, as she is probably dealing with undiagnosed ASD, which is incredibly tough, and girls mask differently to boys, in that boys tend to exhibit similar symptoms, but each ASD girl presents differently.
But that means she should be helped to overcome and deal with the issues (with specialist therapy if necessary), nor pandered to and allowed to destroy the rest of the family. OP’s siblings’ feelings matter too, as do OP’s feelings. Ultimate it may be better to let her live separately, with a little help if necessary.