Dr. Phil has some good ones on relationships. My daughter was daring a real jerk and I gave her the book. She dumped him and never looked back. Your daughter deserves so much more and I hope you are able to help her. Family is important and I don't believe that you should not be involved and trying to make her see the light. After all, they say the human brain isn't fully developed until 26 or so!!!!! Hugs and keep us posted.