What is Happening With Demi Lovato?

What is Happening With Demi Lovato?
I've just heard so many things about her, like she is cutting, she punched someone in the face, she is going to rehab, I just want a story of whats going on because I'm really concerned about her, she always seemed so happy and everything. And what has happened with her and Selena, and where do they stand now?