<human>: Condense the text into a few key points

Yo so this girl and I lets call her hamsauce, well we dated in HS. I was a junior, hamsauce was a freshman. Lost our virginities to each other, basically went everywhere together conjoined at the hip. Talked day and night until we fell asleep, woke up early and talked on the phone. Dated for around a year.

We broke up and after I had a fling with another girl, nothing serious, I didn't really like her much. Eventually hamsauce and I got back together and I told her about said girl. I'm not one for secrets. She was ballistic and eventually cheated on me. I found out, we broke up and that was that. Although that wasn't that, I found out she was sleeping around with many guys and even got a phone call once in the middle of the night that hamsauce was having sex with some douche at a party. 

Well Reddit, it's been 4 or so years and I still think about her regularly. So I ask why? Why can't I get this cheating thieving woman out of my head? 

She won't talk to me and all I really want is 'closure'. I haven't been able to move on. Basically stopped trying for other girls, depressing right?

Anywho I'm fine on the outside, happy go-getter as they may say, but on the inside I still feel broken about what my once 'bestfriend' did to me.
<bot>: Dated hamsauce, broke up, got back together, she cheated in spite, now I still have feelings 4 years later.