<human>: Can you provide a brief rundown of the text in within 3 sentences?

Before I begin, trust me I know I am a horrible human being.

Background:

So, to begin, we fell in love as freshmen in college and it was a wonderful relationship. However, one summer (about two years in) I took a bunch of psychedelics one night and drank very heavily and I ended up sleeping with someone else. He was gone for the summer, so I suppose I could blame my actions on feelings of loneliness but overall they were inexcusable. When he got back I told him about it and broke up with him.  

However, we had classes together, we were drawn together, he chose to forgive me and we tried again. This is really where I turned into a despicable monster. I started treating him so horribly, and I was emotionally abusive. I was constantly trying to drive him away. He forgave me, but I never forgave myself and I should have never gotten back together with him, I deeply regret it. He eventually broke up with me.

Problem Currently:

It has been a little over a year since our final break up. It has been very hard. At one point he tried too rekindle a friendship with me and invited me to his birthday party. That night he was very drunk and told me something along the lines that he believed some sort of fate\destiny would bring us together. After that night he denied saying that or blamed it on his inebriation. Anyways, I tried to go as no contact as possible with him after that night.

But... it seems fate will bring us together, as we are going to the same graduate school. My worry is that being in a fairly small class, we will sorta be forced into seeing one another and hanging out. Should I just lurk in the shadows and be anti-social so I can still avoid him? This might be better for my studies and he was always more outgoing than me. I don't know, I just still feel so incredibly guilty and I feel guilty that he will have to see me for five to six or so more years of his life. Please help.
<bot>: Was a horrible girlfriend to a really nice guy, we are going to the same grad school and I am not sure how to proceed.