My Wife Cheated on me

I recently found out my wife cheat on me with someone whom I thought was a friend.
This all started 4 years ago. My wife and I were trying to have a baby and were having trouble, we were both in our late 30s. She made an appointment with a doctor and we were assigned to a doctor who was fairly new to the practice but came with high recommendations. We saw this doctor a few times and we did wind up pregnant. My wife had a miscarriage though at the 8 week mark and needed a D and C.
After that, we waited some, or so I thought we were just waiting, but we started to try again. We saw this doctor some more. He tried to inseminate my wife with my sperm, but we did happen to get pregnant again. Sadly, she miscarried again at the 8/9 week mark. She was devastated and so was I. On the night of her second D and C, I had no idea what to do. I was supposed to coach a basketball game and did not know that I probably should have canceled but I went to my own place and went any way. I found out the doctor came over and stayed with my wife until I got back.
We stopped having sex. She said she was not feeling good about herself and did not want to risk getting pregnant again. I kind of understood that. This went on for 4 years.
During this time, we became friends with the doctor and his family. We went on vacation together and my wife was the nanny for the kids one summer. Skip ahead and the doctor gets divorced and moves out of his house gets his own place. My wife says she can no longer live in our house with the idea of the 2 lost pregnancies and asks to go stay with the doctor as a place of solace. We hang out, watch college football, hike the Appalachian Trail over a spring break. He and I become really good friends, but so do he and my wife. I get suspicious but always convince myself nothing is happening.
Jump ahead to one month ago. My wife and him have some kind of falling out. He tells her she can't live with him anymore, oh yeah she has basically been living with him for 2 years. She starts to freak out. She is distraught about "losing her friend" can't believe he would just stop talking to her after all she has been there for him. I start to get concerned. I find out from another friend that the doctor is no friend of mine. This makes me upset. One thing leads to another and I find out everything.
Over the last 4 years, my wife and the doctor have been sleeping together. As she succumbed to the anesthesia for the first D and C, he grabbed her hand and comforted her. This made her vulnerable to him. Within a month they were texting and he said he loved her. Within a few days, he was sneaking her in to the hospital to have sex with her. The affair continued as he befriended me and only stopped 2 months ago.
I feel incredibly stupid and humiliated. I can not believe I did not following my feelings that something was amiss. What I really need to know is what do I do now? I have forgiven my wife but I do not know if I should stay. The biggest question I have is do I want to know all the details? What little I do know, hunts my thoughts. I am incredibly angry and cant seem to control it. Any feed back anyone can give me would be greatly appreciated. I am going to see a counselor this coming week for the anger, but how do I reconcile everything? How do I stay with my wife? My faith tells me forgiveness is the first step, but that is a start. How do you handle everything?