Hello, and welcome. There are some extremely fabulous people here with great advice. They will not only support you, but I've found they will be straightforward and hit you with a gentle 2 x 4 when needed..
Anything that you are struggling with, post it and I'm sure you will receive some great advice.
If you want to rage at your spouse, post it here instead.
My best advice is this. If you truly believe that this is over, there is no need to discuss the infidelity anymore. You don't have to explain again why this is happening. Try to make your communications with him as business like as possible, and pretend you are dealing with an incompetent co-worker. If you find you are playing a blame game, don't play it with him. Take your ball and go home.
DO NOT engage with him about the affair any longer. Kids and finances only!!
Focus on you. Do what is best for you. Big hugs!!