Can you trade phones with a sister (so your phone that allows cloud monitoring to see where how much and where he is hiding money which is going to play out for you wonderfully in court when you seek affidavits from the people that paid him) such that you don't read anything about him or relating to him and he can't contact you at all "to go shopping for the kids".

You are "closing the door on a relationship with him" based upon your simply terms - the door will ONLY open (disabuse him of the notion you will ever just be divorced friends with him) if and when he ends his affair(s) and commits to a marital recovery plan. It's his choice.

Right now...by leaving the door a little open you are just continuing to enable the affair and the process of him removing himself from the family. I mean really, a relationship with anyone has to has some benefit to you. What's your payoff for "keeping the door open"? Further, what if repeated what I said before and you believed me "closing the door is actually going to give you the best chance of recovery (personally AND/OR marital)". It will. With the door open slightly still he doesn't have to decide to do anything. He can still maybe sometimes get some of his needs met by you and at other times most of the time met by OW. Nobody is making his choose anything TODAY so why do anything. Going dark will allow you to recovery you whether he opens the door back up to your relationship based upon your boundary or not.

When someone leaves - let them go and don't feel obligated to make leaving easier.

Do it NOW - let him spend the holidays realizing that this is it - OW is his life now and it's all he's got. You know OW is just weak little shallow girl that can't even begin to meet the needs of a entitled wayward husband who's just apparently lost his entire family. Let him feel the entire weight of his non-decision and the natural consequences of his choices because right now - they deserve each other - so let them have at it.

The internet is 90% complaining and entitlement and I hate it because I deserve better!