It is not always the mother's fault! She is making these choices and looking for someone to blame. It's easy to blame the "safest" person. I don't think there is anyway you can get her to talk....she has to decide that it's what she wants. Some of this might be her finding her place in the world, finding her own identity...The only thing I can thing of is giving her some time and when she is ready she will come back to you.
It is so hard to see our kids in pain and confused, sometimes you have to let them go and be ready to accept them when they decide to come back.
I wish I had words that were more comforting. She will find her way back to you.