need advice.........

i am in grad school and my boyfreind of over a year is 18 hours away in school as well. I love him so much and know he is the one. I recently however, did the unthinkable. i drank way too much and hooked up with another guy. I think it was b/c in some ways i am mad at him b/c he left me. of course i told him the day after b/c i felt to guilty. at first he didn't want to speak with me, but came all the way home to fix things and forgive me. He is the best thing that's ever happened to me, how do i let him understand it will never happen again? can this really work? can he really ever forgive me, or will he always look at me and think of what i did?HELP? Tweet