<human>: Can you condense the text into a few key points?

We've been dating for a about a year and a half and have been cross-country long distance for about 4 months now. 
 
I appreciate the fact that he told me, but I am very insecure and paranoid and hate knowing this. 
 
He offered to tell me who if I asked, but I'm not sure if I want to know. He said he felt guilty for thinking it and wouldn't act on it, and I'm trying to trust his word, but you never know what may happen in the future.
 
Long distance is hard for both of us. I think it's harder for him because he's horny all the time - and that's why I'm worried he may one day act on his fantasies.
 
I love him very much and am terrified of losing him. 
 
Any advice for how I should feel about this situation, and his admission? Guys, is this normal? I'm so worried.
<bot>: Long distance boyfriend told me he sexually fantasizes about other girls he hangs out with. Is this normal? Should I be worried?