[vampy]

I'd personally talk to her about it. but not in a judgemental way. the fact that she shows the cuts off to other people suggests its more of a cry for help than a simple coping mechanism.

but then i do like to try and help people. (or maybe interfere? i dont know)

as has been said above, its normally a symptom of a larger problem, and as such isn't an issue in itself (provided she is using clean blades and not going too deep etc). Getting her to seek help about the causes of her behaviour may eventually help stop the behaviour.

there is a lot of information available online about self harm if you wish to educate yourself on it further