Forgiving people and letting go of the past?

ok so i get pissed over the stupidest things.. When I get mad it is really wierd. I get all depressed one minute and then really angry the next. Angry up to the point where I see physical signs. like unable to breath, wanting to murder people (maybe not that much but to fight them for sure) and then sick.. This has started to happen alot! Well maybe not but the things i'm mad about are LONG gone! Some woman at my old church was a mucho ***** to my mom and insulted my family (more than 10 years ago). She said some really rude things. Then there was a boy;-) who broke my heart into millions of pieces after leading me on majorly. this was like 3 years ago. Then i majorly lost touch with everyone i knew from high school and they are mean. I have had many different things happen to me but i think that it's been too long and their lives have gone ahead while I'm stuck where I was 10 years ago.. I am unable to move on. It's wierd. How do i make my life go on again?