[Over]

I think one of the pillars of a relationship is comunication. If you see yourself not communicating something with your wife/husband, that should raise a flag and make you wonder why.

About Dr. Drib's example, I don't think looking beautiful women is cheating, because there's no way you can avoid looking at people and apreciate their looks. It's basic human instinct. The way you act on those insticts or the leverage you give for further thoughts, those are the ones that can be tricky. One can "sin" in their hearts too.

Anyway, I can't agree with Xenophon. People are not always wise or prevident about their feelings. It's entirely possible to make WRONG ground rules and only realizing the mistake when it's too late.

There are social, psychological, scientific and religious rules. The religious ones tend to be more strict, but their moral compass is a perfect God. Everything else is more relative. Anyway, whatever rules inspires a couple, those are needed to make an informed and conscious decision.