"I never believed in divorce but the cognitive dissonance is driving me crazy"
What is driving you crazy is unhappiness...everybody likes to do right, to be the good guy, or girl...But sometimes even good people do nasty things. It's not good to hold an affair for 4 years. It means it's not just an affair, it's something more than that, something you should adress without bias like "I don't believe in divorce". Why don't you believe in divorce? You didn't believe it would ever happen to you, you don't believe it can be used as a solution, you are religious and it's a religious thing? Or is it that you believe that divorce is ok for others but not for you? If it's because you don't want to put your kids through it you must recognize that you already put them through something that might be even worst. Could you elaborate a little more on that?