Well hun, here my verdict. You need to stand up for yourself and what you believe in. If you don't have to right to laugh at the jokes then stand up for yourself. When someone tells you a joke about Self Injury say something like "Hey! Thats not nice! The people who hurt themselves are just trying to find a coping mechanism. It's a serious problem and an addiction!" If they still don't listen to you, then you need to get out of that situation and just not put yourself near those people. Stop lying to yourself and stand up! Remember this! It's better to be hated for what you are, than it is to be liked for what your not.