Be "gay" or be "husband"?

I have been married with my wife for 4 years (no children). Before married, I told my wife one time ual relationship with a guy we both knew. I was going to seperate with her, but she stopped me. At that time, she said she will be O.K. with it. Just recently, she started to think about the past and she sometimes think that I am going some with other guy friends. During these years, I am trying to be a good husband and I am trying to creat a family. However, I feel like that I lie to myself and my life because I am a gay. Sometimes, she rejects me when I was trying to have with her. Now, I don't feel I want to have (even a child) with her because I am thinking to divorce with her and become a gay. I think I believe I am a gay, but I am trapped by those traditional culture. don't know how is the life been a gay. Which will be good for my wife and me? My wife and I had about 10 years relationship. I love her, but I don't want her feel sad if we divorce.