Just be there for her when others aren't. Don't judge her decisions. If that's what she has to do then you can't necessarily force her out of it. By being there for her, she might realize that someone cares about her and that she is loved. Sometimes that's all people need. To me, cutting is like taking a sledge hammer to a Ferrari. There are tons and tons of people out there that will be against that action. Ferrari's are valuable and, whether she believes it or not, people are even more so. There are other less damaging ways to release emotion. Some of them are even fun. Everyone is beautiful and if everybody loved one another then we would be living in a near perfect world. Sadly that isn't the case, but the more people who do love others and have an attitude of selflessness are making it one step closer to awesome. Just love. If you love her, then you just might convince her to do the same.