Diagnosed and want to learn to handle it myself any advice?

when i was 13 i attempted suicide i didnt have a horrible childhood but not a pleasant one either. after trying to kill myself i got taken to a shrink and they keep me on "happy pills" i am now 17 and want to stop being a push over to everyone of my peirs at school but when im not medicated i tend to fly off at the people im most comfortable with IE my feonce and my mother and father. i realy hate myself when i do this though so i know its wrong and i realy try to fix it. Its just very difficult to controll it all the time. Im not a mushy gushy talk about it guy either. My dad was a marine and i was forced into fighting and learning mixed martial arts and weapons training at a young age so the fact that i rarely get in a fight (the onlyones i have been in were i wasnt defending myself was with my dad when i walked away from the house and he grabed me from behind. end result i broke his ankle when i fliped him off of me). i realy want to fix this without a shrink or a magic pill. can somebody please give me advice on this?