If you're in the United States you can join the Army at 17 years of age, if you're emancipated, and probably 18 without your parents permission. You can get educational benefits from them although I doubt that they will fund art school. Just choose a career that they will help you with. You can also get a lump sum payment from them when you're done and you will have an easier time getting some jobs after you're done.
That might be a tough way to get out of your predicament but it's worthy of your consideration.