Your daughter is amazing!

I remember when I was 17 and my mother had an affair with my fathers best friend - I was no way capable or mature emotionaly of having such a conversation with my father. And he was such a hurting man when the bomb happened. He started drinking too much after the divorce and it came to a threshold where he got in a fight with his brother and I jumped in and hit my father in the jaw. After that ugly event he stopped drinking and moved on with his life. My brother and I stuck with him until we each graduated from high school.

You daughters know right from wrong. Show them that you cant have a wayward woman destory you. Dont turn them against their mother though. Maintain friendship with your wife despite what she has done. My father helped his MIL to accept her daughter for her faults. Take the high road Frank.