Somebody said to BH, "Do you want a medal", but do you know what - I really am impressed by her ending it! However wrong she has been it must have taken a lot of strength to stay with this thread and take all the flaming and even though our comments must have upset her, to think beyond that about what people said, admit that what she was doing was wrong (everybody must know how hard that is!), then find the courage and strength to tell him it is over, knowing that however selfish it is to keep him, it is still going to hurt loads to lose him!
I think he has proved how insensitive and selfish he is by saying he is going to tell his wife about the affair, and just before Christmas! And it sounds like he is threatening to do it in order to manipulate BH.
IMO you should NEVER tell your partner if you have had an affair if they don't know already! If you have had an affair YOU were the one who did wrong so why should they have to suffer the loss of self esteem and the betrayal just so that you can try to alleviate your guilt and your uncomfortable feelings of having to keep a secret! If you want to leave your partner because you feel more for the other person I think the decent thing to do is to tell them you are leaving and what is wrong with the relationship without bringing the other person into it. The partner's feelings should be spared as much as possible.
This situation is very sad because it sounds like he will tell his wife and they will split up - for what?! The price he will pay is huge when BH doesn't even really want him! She only wants a bit here and a bit there! He will have lost everything forever for the sake of a bit of secretive sex on the side for a while.
It is sad if he is actually trying to show BH how much he really wants her by leaving his wife but BH doesn't actually want him as much! If this is the case then what she has done by letting it go so far that he has developed these feelings when she has no intention of being with him properly seems even worse.
If he is saying about telling his wife in order to manipulate BH into saying "No, don't do that, I'd rather keep it as it is after all than you tell her, hurt her and then pressure me to let you move in when I don't really want you to" - if he is doing this it just proves even more what a complete bastard he is and will do anything to get what he wants without a care for anyone else's feelings!
BH, have you made it clear to him that even if he tells his wife, you are NOT going to move him in? Sorry if you've said this already and I haven't read it all properly.
I so hope you can all get through this with a minimum of pain for everybody but it doesn't look hopeful.
BH, I hope you have really learned a lot from all you have been through. Anyone who is thinking of having an affair/starting an affair and thinking things like "Well other people do it, it happens a lot so I'm not so awful" or "It's just an easy mistake to make, people get carried away" or "It's just a bit of non-serious fun", I really hope those people are reading these threads because I don't think a lot of people realise just how much pain will be caused to multiple people and to themselves when they start these things.
At first it seems like nothing much when they haven't don't much with the other person yet and it all seems like just a bit of excitement spicing up their lives but my advice would be STOP IT RIGHT AT THE BEGINNING, don't let your feelings develop and don't let the whole thing escalate. You might think you can stop at any time but you WON'T (I know this from personal experience). It is dangerous and addictive, DON'T GET HOOKED. Basically affairs are a bad idea because people WILL get very hurt and probably YOU will get very hurt and that hurt will last a long time. Don't even think about starting one and if you are thinking of it, instead of going for it, look at whether you need to work on fixing your existing relationship or whether you need to leave it and look at whether you really need to work on your self esteem (in my case it was this).