Need some advice on how to proceed.

[michaelCM]

Hi everyone,
First the background: I found out that my wife was having an affair about 10 months ago. (wow, time flies) I confronted her about it, and she said that she had already been "ending" it, and that she was recommitting to us. I asked her to stop having any contact with the other guy, and she agreed. After a while, i found out that she wasn't doing that. She was still contacting him through various means. I confronted her again about it. She finally called him and told him that they couldn't speak to or see each other any more.
That lasted for quite a while, from what I can gather. Anyway, a while back, I discovered that she is indeed still in contact with him. I confronted her again. According to her, he is someone that she still considers a friend, and wants to know that he's okay, so sometimes they email, etc. They also see each other once in a while out at the bars, when she goes out with friends (they have mutual friends and hang out at the same places).
Things have been going very well for us. We went to counseling for a long time. We've connected like we haven't in a long time. I believe that there is nothing going on romantically with this contact with the other guy, but it just sticks in my craw. I can't get rid of it. She promised me that she would stop having contact with him (multiple times), but they just migrate back to each other. It's been hard enough to deal with the affair and knowing the memories that they shared, etc. I feel like Sisyphus: working very hard rolling rock up the hill, only to have the rock roll back down the hill.
I haven't given her an ultimatum to stop it (again), but I don't know if it would do any good. And, maybe it's just me and I finally need to move on, etc., and trust that she is telling me the truth (although, when it comes to the affair, I don't believe I've ever gotten the 100% truth.)
Any advice about what to do?
I want to make this work. I love her. I know that. Why does this seem like such a nagging thing when it might be absolutely nothing.
Thanks.

[Ready2Change]

I strongly suggest reading "not just friends". It has wonderful information on how to heal from A.

"Boundaries" by cloud has great information. Instead of giving her ultimatum's, you give clearly communicate what you will and will not accept in your relationship. You can not control her, but you can control how you react/respond to irresponsible behavior.