I think it is maybe not such a good thing that he accussed you having an affair. I say that because when my ex admitted having an EA, he said he thought I was having an affair. I actually had been under a lot of srtess and was throwing up quite often. I didn't feel like ML and that is where his "assumption" came into play.
So he could be projecting his bad behavior on to you. I don't know exactly what to tell you. I didn't save my marriage as I didn't even find this site until he had already filed. I often think if I had gone ahead and kicked him out... I don't know. We have 4 kids too but they are all at home. I don't come to infidelity much anymore since I am over in Survivng but I will try to keep an eye on your situation.
hugs, kat
Me-53(and learning!) S24, S21, D18, D17 Just keep swimming, Just keep swimming. Dory