Have you read Divorce Busting or Divorce Remedy yet? That'll really help you. Also read some of the article on this site. And the postings on this BB. I find it incredibly helpful and inspiring to read other people's journeys, discoveries, backslides, progresses, worries etc. It's really improved my ability to cope.
No one can tell you if you're just being jealous, but it sounds as though there are certainly signs of an EA. But who knows? Stop snooping immediately - it just gets you spun out and worried. And makes you the less attractive option (not fair, but unfortunately true). Stop confronting him... it only pushes him away.
Start examining what happened in your M that made this happen. See what role you played - again, it's not fair that you have to be the one doing the soul-searching, but that's the reality we all live with. Change your behaviour to change the dynamic that has put your M in this place. That's a really hard process... I know I see every day ways that I was hurting my M, and it's not a lot of fun to look at.
And by saying that you need to change your behaviour, I am IN NO WAY (can't overstate it) saying that this is your fault, that you deserve this, that your H hasn't utterly lost his ever-lovin' mind! I just mean that the ONLY thing you can control is 100% of your 50% of the marriage. You can only control yourself, because our spouses are beyond our reach right now.
Most importantly - get a life! Build a wonderful life for yourself beyond your H and your M. Have fun. That was what I was most reluctant to do, and now it's BY FAR the best thing that has come out of DBing for me. At the lowest time in my life, somehow I'm having a blast. And I was terrified that if H saw me moving forward that he'd feel free to just leave - it I remained a quivering puddle of tears that he'd feel obligated to stay. Well, just like EVERYONE says - it's the opposite. I feel like a Goddess again, and I'm seeing signs that he's seeing me with new eyes. But who knows if now that I'm a goddess I even want this mere mortal?
Good luck and post as often as you need to. It's therapeutic and you're guaranteed to get lots of viewpoints.
