While I can't imagine that your H would have wanted you to continue talking to OM, I can certainly understand how you would have to wean yourself away from him. I have to agree that if you are forced to stop talking to him altogether, there may be the possibility of going back to OM because you would be resentful towards your H.
I Still Love Him:
Why would Prodigal, or ANY person that is having an affair, be resentful towards their spouse for wanting the affair to end? How many people in a marriage WANT their spouse to conduct an illicit affair? It seems to me that any person that would resent such a perfectly reasonable reaction is such a messed up individual that it's not even worth engaging them.