I have read all this and my thought is, didn't you give the dept. store your required two weeks notice? Then why don't you just tell them, you are now finished. Don't go back. All this is creating so much stress for you, the two jobs, the hours, the minimal sleep and this woman whom you work with and lives with you. She also doesn't pay you rent at times. I guess if you gave her notice to move out, then you'd likely lose your job too. That or stuck working in a very hostile environment. I feel for you but you have to start saying no.

If you are at home and she makes her comments, just ignore her or tell her its none of her business what you do. It sounds like you are very much of a people pleaser. I too suffer from that but have learned when and where to put my foot down. I think you really need to just starting telling people, NO. For your own sanity and health. Good luck to you!