Congratulations for being honest with your wife. I know how difficult it can be to embrace your true sexual identity. I am bisexual and only told my wife about 3 years ago about my sexuality. She has been loving and supportive of who I am. That being said, it's been a difficult journey since I am married.
I am in the same boat as you because I can't be unfaithful to my wife. I love her more than anything but that doesn't mean I don't struggle with wanting to be with a man. I had been with men before my marriage so I do miss the physical intimacy of sex with another man. As much as I love my wife, there is one thing she doesn't have that turns me on
You may be going through a stressful time but the most important thing is that you be honest and communicate with your wife about your feelings and desires. Bottling up your emotions and fantasies will only lead to trouble. I know it's a confusing time, believe me I do, but open communication is the best thing for both you and your wife.