Getting a job that pays under the table, getting more education, etc., and trying to save some money are good ways to get out from under Mom's thumb. If she has no money of her own, Mom (and you) are going to have a lot of control over her.
I used to have uncontrolled epilepsy, and at one point (when I was close to graduating from law school) I had run out of money and was living at home. It was horrible to be under the thumb of a bitchy, domineering mother who was unsympathetic to my situation and would put me down whenever I screwed up. (I was too unhealthy to be in law school at that time, but I had been accepted and it was what my mom really wanted and she bankrolled the thing.) At least I could tell her, as soon as I get a job, I'm out of here.
As soon as I got a job, I was out of there, and life was much better. (Incidentally, I am currently a successful slumlord and have pretty much left the legal career behind.)