Self-Injury Support Group
Whether you or someone you know or love struggles with self-injury, this is the community to discuss your experience, find support, meet others going through the same, and get advice on how to stop. Working together, we can help find alternative coping skills to reduce the urge to self-harm.
I'm not encouraging you to cut, but if you really find nothing else is helping, then you need to speak up. Talk to her about it, you never know, she may help you feel better. However, you always need to be prepared for this risk. Maybe a night crying? It's easy to give advice untill you're in the situation.
What I would personally do is try the sutitutes, and if that doesn't work then I'd try to hide it. But that would be the LAST thing I did.