Puppy - you asked for further clarification on my POV of not exposing the affair. I understand it's not a popular opinion and I certainly can only form my opinion based on my own experience but it's just something I feel will backfire on the whistle blower.
I certainly feel for OW's W as I have know when I learned of my H's affair I threw up. And my H's mistress was not married but I knew no matter what "her" status was, knowing what *I* knew gave me tremendous power when it came to the legal side of things even if I never used the evidence I had. I essentially told my H this is what I need and want as far as a settlement goes and you can agree and things will remain quiet or you can disagree and things will be MUCH different.
I simply feel that each marriage must be managed by the two people in it or who used to be in it and it's not up to anybody to "tell" another spouse what is going on. It will come out, it always does. Norm does not know the OW's wife or how she will react on an emotional level with the news her H is having an affair. That alone makes for a situation that could become ugly fast.
It is my opinion that two people in an affair will continue to have the affair no matter what. They simply don't care and are too wrapped up in their own heads and bodies to give a [censored] who knows what. People in affairs don't have a full scope of the consequences.
Right now Norm has hard evidence of an affair and as per his last post his wife has abandoned the marital home. In NY if you leave the marital home and fail to give your spouse written notice of where you will be living within 30 days you can sue for abandonment.
If Norm is not ready to get the legal ball rolling and he chooses to tolerate this on any level, well, that is his choice. But a letter crafted by an attny letting Norm's W know that he is ready to begin the settlement process due to an affair and abandonment will introduce the element of fear in her. It is then that Norm will have full power to handle things as he sees fit.
A WAS as staunch, sneaky and vehement as Norm's (I had the same type of WAS) simply will not budge in their stance or change their actions until a third party (not the LBS or another spouse) begins to pin them in the corner.