I actually had an idea that I might try, see what y'all think.
Instead of telling the OM's W, maybe I'll message OM, tell him if he doesn't end the A, I'll expose the A to his W and make his marriage horrible.
I think it's a better solution than exposing to W, because, this way, he can avoid the issues with his W; otherwise, if the OM's W raises hell, he might just say "F'it, I'm going to keep cheating, the cat's out of the bag already."
Something like this "Hi, This is <me>, Husband of W, I know of your A with my W, and if you do not stop the A within the next 3 days, I'll message your W, and expose the A to her. If you value your marriage and your kids, you'll end the A. I don't care how, tell her you're guilty, you can't do it to your W, whatever. If, 3 days pass, and I find out nothing's changed between you and my W, I will expose your A to your wife"
Thoughts?
M 40 W 40 S 2.5 Together 13 years Married 11 years BD: 09/23/16 PA, then long Distance EA confirmed 9/30/16 Exposed A to OM's W 10/7/16 A ended 10/10/16