When I was 17, my girlfriend (call her Kate) of one year cheated on me. This was not my first girlfriend, but at the time, this was my longest relationship and I thought I loved her. This destroyed me. Before that, I was a romantic, and I approached relationships like something out of a storybook. I treated my girlfriend like an absolute princess. Then she sucked some other guy's dick.

It was like something changed inside me. I suddenly felt: if she could cheat on me even though I treated her perfectly, then it didn't matter what I did or anyone did. Everyone cheats. Why should I be any better or nobler?

During this time, I hooked up with Kate's best friend just to make Kate jealous. I called up my previous ex (Lisa) who still liked me and whom Kate hated, and used her to make Kate jealous. Finally, at a New Year's party, Kate came crawling back and apologized. She had no idea that Lisa had already given me a bj at the same party earlier. Kate and I had sex and got back together - my first time having two girls in the same day.

But i never forgave her. I cheated on her repeatedly during the next year we were together. She probably cheated, too. After a year, i found out she cheated again, i broke it off again, and I found a new girlfriend (Jen).

But by that time, I'd pretty much lost all respect for the idea of monogamy and relationships. I cheated on Jen with Kate. I cheated on Jen with Lisa. I had sex with Kate whenever I wanted, even after she got a new boyfriend (Ryan). Ryan once came to Kate's apartment while I was having sex with her, saw my car, and screamed and threatened us through the window. She went out and calmed him down, came back in, and I finished. Then she passed out and I went home. They didn't even break up after that. I definitely had her a few more times before they finally broke up. Probably because of me. I didn't care.

Part of me hated her for what she did to me, part of me still loved her, part of me loved that she never got over me, and part of me just wanted to ruin her life for what she did to me - and I was armed with the sick knowledge that, for some reason, we were connected and she always answered when I called and vice versa.

I feel bad for how I treated Lisa during all this. Of all the girls, she deserved it the least, and she really just wanted me (maybe loved me) and I used that to my advantage. Lisa and I hooked up for the last time over a decade ago, and somehow stayed friends. She was actually in my wedding party as one of my wife's bridesmaids.

I also feel bad for how I treated Jen, but Jen wasn't much better than me. After Jen and I broke up and I had a new girlfriend, Jen would call me up for booty calls whenever she wanted, regardless of the fact that I was with someone new. She was more or less a male version of me, from what I could tell. She eventually blocked me on all social media. I don't really know what she's up to.

As for Kate, we eventually stopped being anything more than acquaintances. We're actually still friends on Facebook. She comments on my posts occasionally. I live near her sister and we bump into each other at the supermarket sometimes.

It took me years to finally get that anger out of my system. I've never cheated on my wife, even though we've been together for almost 12 years (ethical non-monogamy aside). I've cheated on pretty much every other girl who I ever been involved with though.

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