Use fake blood, it's psychological, the fact that you see the color red can help you to let the pain out without really hurting yourself. It's not really 100% effective and the mental pain is still here but i guess it's better than actually cutting your wrist. Take care, life is short and don't be afraid to seek fir help. The most courageous act is to accept that we need to be helped. (Btw sorry for my English, it's not my native language I'm french)