I think that people think that if they can see or be with their (cheating) OH all the time, they won't have the opportunity to cheat. And then they can convince them how amazing they are, and give them loads of sex, or be amazing or show them what a good family they are or whatever and they'll forget the OW.
I had a partner who (because he was a cheat) would try to give me comfort by turning find my friends on, phoning me constantly, be with me all the time. But you can't stop them on social media, even if you can stop them going out. And it's just tiring, and anxiety making and demeaning.
But cheaters will find an opportunity to go out or they'll spend the time messaging anyway and at least one of the affair partners will think they are in a thwarted love story.
And even if you could make them see how amazing you are, it's such hard work and why would you stay that person? Everyone is worth more than that.
I also think there'll be lots of divorces after this - probably for the more mundane reason, that people just don't really like each other as much as they once did.