It has been my experience that "wherever you go, there you are." If she is moving away but is not working a program of recovery, then she's doing what we call a geographical cure. It's the idea that things are not working here, so I'll move over there and it will get better. In my world, all that means is his address has changed. The problem moves with him wherever he goes, since the problem is within HIM.
You can make changes and set boundaries, and it could be a good exercise for you even if she's only going to be there a few more days. It shows that YOU have changed as you've found your own recovery, and you can establish the new ground rules for if/when she comes to live with you again.
Mom hugs.... this mom stuff ain't for weenies.