oh ((((((((((((ww))))))))))))))
it sounds like you have a daughter in so much pain. i would wager money on that she has some very severe attachment issues, combined with a deep hunger for love and acceptance- a incredibly painful combination
i don't have to walk in your shoes, so far be it for me pass judgment on any decision you make, but my heart bleeds for this young girl. she needs a loving mother, even though she rails against it. i say get the restraining order and do whatever you can to help her while you still can. from someone who has railed against a "mother's" (my T's) love plenty, i can say that sometimes when it seems you aren't getting through at all and it hurts like hell to try to love someone, you can reach them in ways that you can't see and you can help them find their way out of crisis. T did that for me.
you can't save everyone, though, as terribly sad as that is.
please trust your heart to know when you have given everything you can and cannot go any farther.
sending you many wishes for strength to sustain you, clarity to help you see what needs to be done, and love to inspire you and keep you willing/able to do what you must...