You're not a fool, unless loving and trusting someone is foolish.
I understand the feeling though. I feel like a right idiot for leaving my family, friends, career, my country, for someone who clearly never valued me.
Sorry to hear about the possible OW. Take some time to digest this. Don't do anything yet. Now you've asked the question of him, just leave him be. Ignore him even.Tine to regroup and reconsider.