Gosh, thank you all for so many thoughtful responses. I will try to respond fully, but if I miss you, I do really appreciate that everyone has been so kind, and trying to help.
So, I can see that my first post sounds awful. My mum isn't abusive, I think it would be massively overkill to cut her off. I get spaced out around her, and self-harm and all, because of what I associate her with, which was abusive, but that was mostly my dad, who's dead now anyway. Mum can be mean and critical, and she's especially hard on me for sure. But she's not really hit me or anything since I was a child. She was just there and like passively enabling the abuse.
@CantBreathe90 yeah, you are right, I know. I prob should have said at the start I do have PTSD, so there is something wrong with my mind. I do want to get better and am trying stuff, but tonight was a bit of a set back. DH knows I self-harm. He's not happy about it, but he isn't going to make me stop.
Gaining weight is not really an option for me, I have had anorexia and it's kind of still hanging about tbh.