The way I see what you describe, you have some choices here. Choices that NO ONE can make except yourself. So, not "advice" per se, but just a bare bones outlne of the reality you describe, which sounds pretty damn horrible.
A. If your mom hasn't changed her behavior or how she interacts with you in all these years, she's most PROBABLY not going to. She would need strong motivation (or emotional shock, which may not be possible for her) to learn, grow and be different. We can't make people what we want them to be. And no amount of bearing the burden of personal suffering will karmically alter things to your liking; it's just punishing yourself further.
- choice: you can simply continue on the way you have. you have the freedom and agency to do that, if you choose... and no one can judge that, ethically. you will probably also continue to rail at the godz about the fate you accept with this choice and feel stuck.
- choice: YOU have the ability to change your behavior and level of interaction with "mom", at will. You can choose to live your life with almost no contact to absolutely no contact with her... and no one can say "boo" about your choice; it can't be criticized or judged by anyone else because they aren't YOU and don't have this ongoing repeated nightmare sham of a "relationship". What you do with the extra space in your life, is again, up to you.
- choice: YOU can reclaim power over your own life and slowly but surely, work toward making a contented and comfortable life for yourself. Yeah, it might mean allowing some friends gradually into your concentric "circles" of trust and confidence. Yeah, you might be dependent in ways on "the system" until you get on your feet. Yeah you might have even greater challenges... but it sure as hell wouldn't be boring! It could be the adventure of a lifetime to design, develop a plan and execute it to build your perfect (or as close as any of us ever gets*) life. *= none of us have a perfect life, and most of us struggle with various things at various times, for various durations. Even the "celebrities" have their own struggles and agonies... bless their hearts.
- choice: you can just aceept what you're currently experiencing as your lot in life and give up trying to be who you really are; or decide this IS who you really are... the choices and combinations of choices are pretty limitless. But only YOU will know which one(s) feel right for you, that you like/can live with, and will propel you closer to what you can't even see right now, that you might really want for yourself.
B. We only get this one life, with this one consciousness. I'm allowing for the possibility of reincarnation - which presumes that one would have a different consciousness. We all have tests, struggles, challenges, horrible experiences - and absolute grace from the godz - in our lives. Do we always see these? not necessarily. Do we have to consign ourselves to a life/conditions/circumstances that is just the first challenge of what we were born into or can we find our inner rebel, and "go do" something ELSE?
NONE of us know 100% which is better; we don't have crystal balls about the future difficulties we'll experience on either path. And no one is "perfect enough" to judge you on what you choose for you.
Good luck, Sis.
(typos corrected for clarity, given I've had a bit too much coffee)