HC, I think your session went well albeit painful.
The fact that your WH opened up with something you can work on is good. Having him move out makes it difficult to really start working on things, but he may be so miserable to be around that it makes it Impossible to work on things.
Yes he is a cake eater but let him know that you will not participate. If he wants the OW, like you said you can't stop him. But tell him that it hurts you and your anger comes from the hurt. And if he continues his EA (which is no less painful than a PA), that you will no longer be his wife. Not talking divorce just yet if you can handle it, but no "family" get togethers, no coming home uninvited, no phone calls, emails...disconnect from him and take care of the kids. I know this will be hard, I am trying to do it right now...but we must do it. Confirm that you love him but can not be a part of his life as long as OW is there.

Is he refering to other anger within your marriage? That is my husbands crux as well. So I am working on how to express myself in non angry ways. Christmas will be difficult. I would tell him that if he ends the EA then Christmas can be your new beginning. If he does not then he is not welcome.....

I stayed home yesterday just for a good cry, because I asked my husband some questions about the A and rebuilding trust and he refused to answer. I wish he would tell me what the hell is going on so that I can use that information to decide where I need to be and how to proceed. You have the info, now it is up to HC the woman who deserves love and respect to decide what is best for her. Good luck and keep us posted

WWH