My experience is that once you stop talking about OW things will improve. Unfortunately although it hurts, now you know how H felt. I'm not saying that to upset you or anything else. I think he has been very vindictive and petty in some ways. Frankly, he has to forgive you if you are going to reconcile. And forgive wholeheartedly. That is a very difficult thing to do.
If he has been talking to this person for a while then likely there is a need that was filled and it will have to run it's course. There is nothing you will be able to do or say to make that happen any faster. Now is where you have to decide what your limits are. Are you willing to tough it out for a bit or not? Is this a hard line for you?
