I don't mean to sound critical... just some quick observations:
...it sounds like you are relying on OM for validation and feeling good about yourself. That seems kind of sad to me.
You write about your husband denying intimacy, but you are doing that. By hiding your feelings and not sharing your thoughts or "making waves" you are withholding intimacy. If your husband is depressed, perhaps antidepressants would help? And if not separation may!!! I know that sounds nutty, but your husband may be more unhappy in the marriage than you think and a separation may be painful for him in the beginning, but in time he may learn alot about himself, grow and become a better person (I know I did! In the long run it was a good thing!!!).
You might be right about OM not being affected by the emotional affair. From what I've read men usually compartmentalize relationships while women romanticize them.
But do you know for sure you're not harming OM and his marriage and family? If you do care about him perhaps you should consider discontinuing the relationship until all the kids in both families are grown. That way there is no chance of hurting the kids and creating a potential mess. Then, once they are all grown you (and OM if he's still interested) can figure out where you want to be.
