While I have never experienced infidelity in my marriage, I will say that I probably COULD forgive my W and take her back.
But, the nagging thing about it is that I would always have it in the back of my mind that if she did it once, she could very well do it again. The luxury of the benefit of the doubt would be gone forever.
Yes. In the early days of our marriage, my wife (and I, for that matter) was very unhappy, and had a couple very intense EA's. If I had been a member here in those days, the advice would have been to divorce her, and we both today acknowledge that we were completely off track.
Today, our marriage is the best it has ever been. To be honest, trust perhaps will never be complete again, but it doesn't define our lives.
Complete openness and honesty is the key, and in some ways those experiences have helped us understand what is needed for a real relationship.
It is for that reason that I shudder when I see the automatic advice so often given here to give up.