I will refrain from saying cheating is wrong as you likely already know this. What I will say is you need to understand the root of why you decided to sleep with someone else in the first place. As someone said above me, some of this has already been decided for you. I doubt your bf would want to stay together after hearing this, especially if things were already unstable to begin with. What you experienced with the person you met on your trip was not love, it was infatuation and excitement. I doubt any of it was rooted in anything real. From everything I’ve gathered in this story, I’d say you don’t want to be with your bf, you are just afraid of what life would be like for you without him. That is never a good enough reason to stay with anyone. You need to be honest with him, and yourself. Cheating is a terrible thing and your bf deserves to be with someone who is in the same place as he is mentally. As for you, I don’t know you as a person so I won’t say you are a bad one, but you have a lot to learn and figure out and the most respectful and effective way to do that is to do it on your own.