____________ (mention name of your wife),
Dear _____ (Name),
I write this letter with my heartfelt apologies. Through this letter, I would like to apologize in front of you and present that I’ve been cheating on you for a very long time.
You have been the perfect partner that I could ever have. You have done a lot of things for me and you have always been supportive to me but I regret to inform you that I failed in making this relationship work. I don’t think that I could do anything good for you.
I would state that you are a very good person and deserve better company than me. Once again I apologize for cheating you and hope you can forgive me
_____________ (mention your name)