Sorry for asking this if you have already mentioned it, but do OW and her H have children?

My sitch was not unlike yours and I was the last S to find out. OW had already moved out and was waiting for my H to make the next move. I was able to put a stop to it once I knew about it and my kids also helped. My H couldn't believe how horror struck they were by what he was doing/planning.

Saffie
me 46
H 46
M in 1986
D20,D18,S16,D13
H's A 01/05 to 07/06
H recommitted to M 07/06
renewed vows 09/06
Going from strength to strength