After all these years, maybe its time that you accept her for who and how she is. Its not you..its her. Don’t let it define you. I know its easier said than done but I see a lot of people that are troubled and indirectly reflect there relationships with parents in there own lives. You cannot change your mum. She is how she is and her attitude and behaviour is not your responsibility. Just love her for being your mum. And love yourself for who You are.
Regards
BU