I don't have any idea what to do in this situation?

My girlfriend is severly depressed because her parents are controlling. She asked me if I could talk to my parents about her moving in with us. She doesn't like her parents. They restrain her and cut her hair the way they want it. They read her diary. And they won't let her take any of the cles she wants to at school. She is very sweet and doesn't deserve to be treated like that. She cries and asks me to hug her. What can I do for her?