How do you feel about people in monogamous relationships?

Bit of a weird one but yesterday I came to the conclusion that I look at people in monogamous relationships the same way I think about people who are religious.

I'm not here to rage bait or religion bash but in a weird way I'm quite jealous of people who can think that the world was created in 7 days by the all seeing man in the sky, similarly I feel like wouldn't it be nice to just be in a happy bubble where you think everyone is going to be Monogamous and everything is happy with your current partner. Still I just can't shake the feeling that people in affairs are the "red pilled" ones for lack of a better saying. I feel like in every relationship one person cheats so I'd rather it be me? Perhaps I'm just jaded and being a typical guy but seems to fit