I will never say my SO would NEVER cheat but I can say he would never cheat without telling me first. (Telling me he is unhappy, asking me to talk to him and fix things) we are 100% honest with each other. We communicate both good and bad feelings.... we both know that the other person can not fulfill all of our desires and have to find happiness outside of strictly our relationship. I've been cheated on before and I know this man is different because of his maturity and acceptance of himself. He is not looking for validation anywhere else. Besides, he never shuts up about me or my daughters so he cuts off any interest at the pass :)
I know he wouldn't now because we have both cheated on one another and got caught. It was hell for both of us and now we just want to focus on making us work. I'm not going to live in fear of him doing it again. That's not a life. It is possible to rebuild trust after an affair, but it takes lots of time and patience.
I don't think my fiance would ever cheat. He's not that kinda man. Which I know is what you are questioning. I was cheated on in the past. I know what it's like...I know what I went through with him to understand what was going on in that relationship. He made a fool out of me to our friends for 3 years. THREE YEARS.
In this relationship, I chose my partner more carefully, and am confident that my love is enough for him to be happy and to stay faithful to me. That is why I don't think he will cheat.