<human>: Ok. It's a long story. 1.5 year ago I worked with this guy I really fancied but never has done anything to show him that I cared. It was too complicated we both had steady partners and he had a child. For these reasons I never tried anything...

Once he talked to me how unhappy he is and we started having regular chats on how our relationships suck. From word to word, we ended up making out. Just once. But I felt so terribly guilty. My boyfriend has never found out anything neither have that guy's girlfriend.

I know what I did was wrong. I regret it. The problem that I have now is inability to move on. I regularly check that other guy's facebook, his now ex-girlfriend's facebook too. I'm obsessed. I'm pretty sure it's not about loving this guy because I don't. It has to do with the feeling of guilt... i don't know how can I feel at peace. I dif not agree to a long tetm affair, but I should have been more responsible and just not let anything happen. It's been 1.5 years..

Give me a shortened version of the text
<bot>: Cheated on my bf 1.5 year ago and can't get over the situation. How to stop being obsessed about that past?