Here's the best case scenerio...but somebody is going to be rightfully pissed off & somebody is going to have egg on their face & need to kiss a lot of butt. However, you will definantly have your answer.

I do agree on the surface you did a lot of prying over something so trivial..the email said "Hi"
However, sometimes a woman's gut is an instinctual thing & sometimes it's just insecurity.

Here's a gutsy offer. You push him to let you see all the messages he's sent her on that spot immediately. You may tick him off because you are letting off some serious vibes at this point. When this is over one of the 2 of you are going to have every right to be mad, one of you are going to have egg on their face.

Assuming he gives you access to the letters...then you will know if it was innocent or something more. If he is involved with her, he's busted & you have your answer. If he didn't....he's going to have every right to be pissed at you. In which case you need to appologize for being insecure & say stuff like "the though of losing you just drives me crazy" Make him feel like king ***** for a couple weeks & he will probably get over.

The question is, would that temporary embarassment be worth the piece of mind of knowing from that point on you have a decent man.

I agree with both other post. There isn't much evidence but also doesn't completely past the smell test...Your decision...I would risk looking like a fool for a little bit to feel that I wasn't played for a fool