What should he do to this non-rent paying guest?

One thing led to the other one faithful night after work I came back and she was lying on the couch almost half naked, after taken my bath , she got up and before you know it we started having S£x. After that day it became routine and I have a fiancé at same church.

My problem now is she has stopped paying rent over 10 months she has not paid a dim, she doesn't pay bills again, even when my fiance told her to look for alternative accommodation, she has refused and I am reluctant to tell her to pack out because of emotional attachment.

Now what do I do ??