I don't know if there could be complete closure to something like infidelity, I'll spare you the details but it is almost 3 years now that I have tried to put closure on a similar situation, time,therapy, and medication have helped but I still wonder how much is still a lie to the fullest, he traveled on business with this ***** co-worker, things got too close for comfort for me when I came upon something I was not meant to know and that is when I went berserk, I never had a major problem when I knew they had to travel to Europe, it was understood there were others from the company too, but later I found out about him and the secretary who also was a friend of this bimbo, what a pair these 2 were, I better not get started, ha!ha! I'd like to believe nothing happened, but really when you lie about where you were and who you are with when like I said it was always an open understanding and I had trusted him till I discovered the lies, etc. that's the moment I knew I was being made a fool of. I would advise couple's therapy, if he refuses to go I suggest you go alone then, besides working through this with a therapist you may want to work on the WTC 9/11 trauma too, it may help. I have a cousin whose daughter also was one of the lucky ones that just missed it as she was approaching the first tower to get hit, she had worked there. She was so traumatized by the horrible devastation and loss of her co-workers, at first when counselling was suggested to her, she said "I'm fine", but her family saw there was something not right, she may have been in denial, like a defense mechanism had kicked in but as time went on she realized she needed to have someone help her through this. The cheating thing, that I wish I could give you more positive info. but I myself am still "healing", we've been married for 25 yrs. and knew each other since we were about 13 yrs. old. The trauma that you went through with the WTC was horrible but you had visual proof of what happened there and then, confirming in your mind, but I think it is more of a trauma to ourselves and relationship when you find out the person you always trusted has not been trustworthy..
Also as advice in choosing a therapist I'd go with a woman, I get along well with men but found that they sometimes lean towards defending the cheater if the cheater is also a male.
But that is just my opinion only, and if possible I hope my 2 cents can help save you further anguish. Please take care and always remember your kids are most important regardless of what happens with you 2, I mean it matters too but the kids are what we live for

"darkeyes"
In giving advice seek to help, not please your friend
SOLON