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

About two months ago, my boyfriend (19M) cheated on me (19F) with his close friend from school about 5 times over a period of a week while under the influence of cocaine. I can honestly say that I have never been so devastated in my life. To make matters worse, he continued his friendship with the girl (they did not hook up again) without telling me until he came home for summer. His excuse for this was that he had no other close friends at school (we go to college in different states) and he was extremely depressed. 

Now that he's back he's blocked her and deleted her from his phone and social media. He answers all questions I have, lets me go through his phone, and tries very hard to make me feel better. I'm extremely paranoid that he'll continue talking to her once he goes back to school.

 His cheating is all I think about and it has become almost an unhealthy obsession. I don't seem to be improving no matter what he does to try to help. I'm still in love with him and I'm worried that I'll break down completely if we go our separate ways. As of now I want to try to make it work, or at least maintain a strong friendship. How can I start to forgive him and more importantly, how can I begin to heal? Any advice is appreciated
<bot>: my boyfriend of 6 years cheated on me, continued talking to the girl for a few weeks and I cannot stop thinking about it. How can I rebuild my relationship? And how do I move forward and stop obsessing over it?