Even though going into debt would suck, maybe you could try loans? You'd have to have
some sort of schooling plan in place though, and in a field where you could get a job
pretty quick to start repayment. I have a friend who lives off loans and a really lame
part-time job. Maybe if you did that and your mom saw you working toward your
goal on your own, she'd be more inclined to help?
Or you could tell her that you'll only help her as much as she helps you. If she thinks
you're just supposed to be there for her whenever to do whatever, then it needs to
be a two way street. It's not fair of her to expect that out you without something
in return. You're not supposed to have to tale care of her, she's the mother - not you.