I think you should go to the libraries in your area and check out about jobs in them. It might really make a difference, if they have anything it'll likely be some steps up from retail/food service. Or maybe check with your college? I had a work study job as a secretarial assistant at mine while I attended and it was the beginning of a long line of office jobs (which pay more and have more benefits than retail/food). I think you probably aren't sabotaging your jobs though, they are jobs that tend to treat their employees as easily disposable, that's not your fault. If they don't want to even try to help you improve and would rather passive-aggressively remove you from the schedule without outright firing you, it really shows badly on them on how they treat employees.

I think you should just look on moving out and on to better things if you can. I know it might be hard finding another job right now in this economy but you aren't actually working right now anyway!