Sorry to hear about the luck my man. I went through something like this a couple of years ago. I was with a girl for about 3 years and I considered her my best friend. I thought I'd never meet another person like her. We lived together and I never thought I'd have to worry about anything.
I walked up to a party one night and saw her all over our neighbor.. who was also my friend. We fought about it, but I figured it wasn't THAT bad because I only say them sort of flirting. Needless to say, shit got fishier and fishier... one night she didn't come home after going out. I stayed up all night waiting on her. She texted me in the morning and said something like "oh I fell asleep at so and so's house (one of her girlfriends) I'll be home soon." So I went outside and watched her walk out of our neighbors house. She had been ******* around on me with this guy for awhile.
And here is where the story get's particularly important for you! Me thinking that I'd never find someone else like her and me not being able to move on, well I took her back. We got engaged after a few months of working things out... which was obviously stupid. I eventually found out she had cheated on me other times... one of which was with one of my friends after I took her back!
That being said. Move on. If you guys were first love and first everything else, then you need to get some new girls.... and she's going to have interests in other new guys. You can't end up with your first person. And, you shouldn't go back to someone who wasn't faithful.
Move on. Trust me, there is nothing better than getting some rebound, no strings attached booty.
"Existence precedes essence"
- Jean Paul Sartre
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