I was bullied at school. Now I enjoy hurting people?

even though you are on the high end of the extreme here, what you're saying and feeling is not totally crazy. that's just like when boys are abused by their fathers, or see their fathers abusing their mothers and they equate all that abuse as being totally normal and even an indication of love. one of the guys i am really good friends with and care about a lot is kind of like this. He enjoys seeing the girls he truly cares about in pain (whether it be emotional or physical), just for his own pleasure. i guess it makes him feel in control again. But connecting this to you, clearly you are not shining as you say because as you pointed out on your own, you have nothing. And your claim of only hurting people who insult you is kind of insane because everyone in the world will hurt you in one way or another, but you have to deal with it somehow other than physically harming them.This is definitely going to get me a lot of thumbs downs, but I shall say it regardless. I think you're a good person deep down and this is how you have learned to deal with pain. I say this because my same guy friend has a lot of hurt too and I excuse all his erratic behavior because he has opened up to me about the pain, so I understand him. I feel that him having me to understand him, makes him feel so much better and it kind of frees him from having to hold all of that in and battle it on his own and now he has someone who he can let his guard down with. So to my suggestion, I think you need to find someone who can help you and understand you (as I did with this guy). It can be a girl, or a parent or even just a friend. You need someone to help you soften up and realize that it will all be okay. But until then, have you considered therapy? Good luck and keep searching for good people, because they are out there! =)