Reply to comment

Longstanding marriages typically do not end after a single incident of infidelity, so I don't see your point. 100% compliance is not absolutely required for a strategy to be beneficial.

A couple that has been married twenty years with three children typically does not end the marriage when one party has a drunken one night stand.

And you completely overlook the fact that fidelity helps them get through those twenty years by shielding them from the open-ended potential for complications in an open marriage. If you're fine with your spouse sleeping around you increase the risk, for one thing, that your spouse may conceive a child outside your marriage. Or contract an STD. Or attract the attentions of a troublesome person. Or leave you flat. These consequences will not help your marriage.

You simply don't notice that working to avoid these risks benefits the marriage. Even if someone slips. All you see are the tears when an infidelity is discovered.