pinkbutterfly, I don't think you would be "mean and cruel" for asking her to find other arrangements. You have done your best--and I, too, think you need now to concentrate on yourself and your boys. I hope she doesn't try to make you feel guilty or act like she's going to fall apart, etc. when you tell her. But if she does, then you can't give in.......

As you say, she is an adult.