There is also one important factor I left out. I believe in my vows. 'Till death do us part; for better or for worse. I planned on being married for life.
This all came about once I confronted her about the affair. Until then, we were just fine from my eyes. I would always ask her how we were doing. She would say fine. Until this came up, I had no reason to worry that I can think of. Sure, we had passing comments but no real fights or problems. Even after the confrontation she said we had always been friends; she just didn't have the passion for me that she has for him.