Oh good grief. That DOES put another spin on it.

Get her signed up for public housing/food stamps/Medicaid and of course she'll have a case worker. Let the case worker know that she's mentally ill, and perhaps they can get her to see someone. Then you can get her out of there once they place her in housing.
Hopefully it won't take TOO long. It shouldn't I wouldn't think, unless there's a waiting list for housing.

I sure hope not.
Please keep us informed on what goes on, will you? Perhaps someone else will have better ideas. My prayers go out to you. i don't know how you've stood it this long -- you are to be praised for taking her in and being so kind to her all this time. Not very many would do this. You're an extremely kind person and I applaud you for that.

God bless you dear one, and please take care. Hugs, Lee