I think im depressed but i dont know what to do...?

i write this because i feel like im slipping. everyday i battle with the idea of killing myself or others. i just don't know anymore. i want to live and be happy but i don't know how.i like helping others and it makes me happy but everyday i struggle with the fact that i like to hurt others and it makes me feel good. better then when my parents tell me they are proud of me and more then when my friends say they need me.everyday i feel pain, emotional and physical pain and i feel like i must spread this to everyone i touch or it will become greater. im scared, everyday i fight this and ive won thus far but i dont know how much longer i can last. i dont want to be his way but when these thoughts just appear, how do you combat that. how do you stop your mind from thinking? i have found outs but it is at odds with my friends and i dont want to loose them. im afraid... i feel cornereded. ive got my back to the wall and that dark impulse is getting close. i cant see it but i feel it everywhere and ...im really scared. i want to join the millitary to kill others hoping i can feed it and it will leave me alone but i know in my heart it wont. i dont know how to stop it and im thinking of giving up. is this who i really am vs. who i have been tought to be or is this my good nature vs. what everyone fights. i dont know if im alone or not. i know there are others like me but how do you find them. i know im ashamed to be me so i ume anyone feeling like me would be too. so how do i find comfort. i have no goals...i have no companion to spend my life with and tell that i love her and trust myself with. all i have is the thought that i should be better and ... well thats all i have when it comes right down to it. i am the only constant in my life. im alone. so what now. its just me and my ... i don teven know what to call it. my envy, my greed, my wrath,my pride? im guilty of so many things... im tired of acting in secret and telling nobody but that only hold it back for so long. it becomes harder to satisfy everyday. are these foreign thoughts or am i? is it possible that i am the intruder in my mind? meant to be somthing else and let this, this thing run losse? am i the thing? am i real or is it? am i it? am i the monster and just now coming to see what i am? is that ok? do i have a right to live knowing that i only want to hurt others? if so what now?