Have you thought of trying to get her to go into counseling, either by herself or with you? It may take awhile for the first appt. but if you go to your local mental health clinic they usually will charge on a sliding scale. Although I have to say it sounds like a month or two wait may not work for either of you.
If one or both of you decide to not try for counseling then, yes, it sounds to me - all this just my opinion - that the best thing to be done for both of you is for her to go live someplace else. Maybe you could still help her financially, if you felt it was what you wanted to do. If not, she has to learn what her new reality is and how to take care of herself and find a way to support herself. She may be better off doing that in the long run.