I (33M) am in a situation very similar to that of OP's. Maybe one can say that the stakes are a bit higher. We (33M and 33F) are in relationship for two years and have married last summer, we also have moved countries together. I have met someone and fell in love, confessed, and found out that my love was unrequited. Now I can't pretend that everything is as usual with my wife. And yes, we had wonderful moments together, and I loved her, but now it's gone, and my failed crush illustrates this with a very blunt evidence.

I realize that I have to be honest with her and break up. I see many comments here asserting that it is the "right thing to do", and I agree. I told her that I wanted to break up and divorce but I couldn't bring myself to tell about the crush that sparked the breakup, knowing that it will hurt her even worse. Actually, some long time ago she told me that I ever cheat her, she would prefer not to know. The result is that she doesn't believe me, and thinks that things can be fixed, and refuses to let me go.

I don't know what to do.

Guess I should man up and end this all anyhow