Replying to How do I get this girl off my mind so I can study

so this girl and I started out as friends and we used to just kick it all the time... then realized we both wanted to fuck so we did that. And since we've been friends since before we had good chemistry and could talk about anything with each other. We still called each other "best friends" but who are we kidding I was in love (still am). Anyway we've been apart for a few months due to school and won't see each other til new years so now we're just snapchatting very occasionally. I just want to look in her eyes and hold her and kiss her again. One night stands from the bar just aren't the same anymore and I'm having trouble making connections with other girls which is unfortunate.

see the thing is... she's had a boyfriend the whole time. If she'll cheat with you she'll cheat on you typa thing. And IK she's known to get around a bit. So I knew from the very beginning I'll never have the relationship with her I want. I knew the truth from the beginning but can't get myself to believe it. Once I got a taste of fucking my best friend I was doomed. but right now I gotta study for school goddammit so I can't drown my sorrows in liquor drugs and meaningless hookups. What do I do.