Recently, I did a terrible thing in cheating on my long-distance girlfriend. I have been reading relationship counselling websites about how to address everything moving forward but I am having some issues. I have gone to my partner and told her the truth of what happened. I read that it's best to not give every painstaking detail about the event so that the imagery that haunts me isn't as detailed in her mind. I feel like this is the right thing for the sake of our relationship but I still feel a lot of guilt about knowing things that she doesn't. Also, from the advice of these websites, I have been trying to reflect on myself and figure out why I cheated. Many cite different possible reasons but I can't seem to find one that I feel properly describes mine. I'm not a very sexually driven person by nature, so I really don't believe that I was just deprived of physical contact due to our long-distance situation. And I definitely am not attracted or interested in the person I cheated with. She is an ex of mine that I separated with on mutual terms, but I can honestly say that it's been quite sometime since we were together and I in no way find her attractive anymore. The whole time I was committing my act of infidelity, I was thinking that I had no idea what my girlfriend was doing away from me and that there's no way I can know she's not doing the same right now. It wasn't until we had already began to have sexual activity that I stopped myself and was overtaken by remorse. It might be pertinent to mention that I was drunk at the time, having just left a party. Given all the factors of what happened, I feel like there should be more of a why to what I did than just an inconsiderate sex drive. I feel like I need to find what is wrong within my own head that caused me to act this way, and address that. I know for certain that I will never do anything like this again, regardless of whether or not I am able to repair my current relationship. But, I'd still like to fully understand what was happening psychologically at the time so I can work on fixing myself moving forward.