What is the right thing to do?

I ment this girl in 10th grade I was 16 at the time she was 15. I had he in one class and didnt see her again for like 2 years and then she came back into a class I had. Ill never forget that day she had the most amazing hair blonde and a nice smile and amazing body and she sat down and smiled at me. From that day on we hit it off. Throught out the years between this time I had had sex with several people I was young dumb and full of cum and loved to party. So we started dating shortly after I was the first person she had sex with. For a year everything was great until I asked her about a guy from her work she tripped and was going to a partry of a mutual frined of ours and I asked her to wait till I got off work and we could go she said I was being to controling and wanted to split. WHO WAS SHE AT the party with the guy Travis I didnt waste any time and went up and threw him againt the wall and proceeded to beat the shit out of him. She left with him and he was pretty lit up had a busted lip and a swollem up eye and was limping I felt good but only I did. So her friend calls me and I said I love My gf and I just want to work things out she held up the phone so I could hear them two having sex great My heart just broke I felt my stomach drop to my feet and I said fuck it I was at a party and took a girl home AND FUCKED HER FOR atleast 2 hours straight and took another girl home the next day from my science class and fucked her and then ment up with a girl I ment off myspace went out to a movie stayed at her house and fucked her then a week went by and it was random girls here and there and I felt like I had moved on even though I still loved her then she calls and says shes sorry but doesnt inform me and I dont figure out till 3 years later she also slept with our mutual friend We get back together things are rough at first and life continues for another two years after the first break up her friends started to despise me and that was fine I was happy so was she but I began not to like them when they said well shes coming out with us tonight I didnt want to say no and sound controlling so I let her go and the whole time they were trying to introduce her to guys I let her leave on a trip to a snowboardiong resort for a weekend were she cheated on me 3 days before vbalintines day And then left me I got to go finsish a little later