@deadmailrock
He didn't know she did that at all so he didn't feel betrayed or hurt, that is what the story has shown so far. He is knowingly neglecting his family that as far as he is concerned, everything else was normal. I doubt the story would be any different if she had actually slept with him. Either way, he neglected his wife and biological son(as far as he is concerned and the story hasn't said otherwise I think).
I think the wife wasn't hundred percent right in her method, but she dodged a bullet kind of by not sleeping with that man. It would have been a complete waste of her life to be there if it wasn't for her son being born out of that marriage. She did the right thing considering the nature of the guy she married, unless he acted like that because he figured her out(which is unlikely).
Oh well, let us see where the journey takes us.