Something similar happened to me once. Rented to a boyfriend/girlfriend, they split, she moved out. New girlfriend moved in, they split, he moved out. Then, I had a woman living in my rental house that I didn't even know. But, I had no lease with her, so was able to get her out fairly quickly for trespassing. This was in another state (not NM), although I live here now. If you'd like the name of an attorney that can help, let me know. I have a local one that deals with this sort of thing here in ABQ.