It sounds like it's difficult for you to find an other job and a new place to live, is that so? You really shouldn't have to put up with your sister's behaviour. Could you just stop cleaning up after her? Do you think she would clean up after herself if you just left the mess for long enough? Or would it just make your home unbearable to live in? I understand very well that you're angry. Anything you can do to take care of YOURSELF, you should do. You deserve so much better than this!