It is my sincere belief that the male human is inherently polygamous. The reality is that of the several ways a man can deal with this, none are particularly condusive to complete honesty.

A man can rely on ethics and love for the woman in his life to ignore those natural urges. But he better not let on that he has them.

A man can simply act on those urges and not tell the woman in his life. I believe we call this cheating.

A man can fantasize about others, but never actually initiate contact with any other woman.
Again, it is best that he keep those thoughts to himself.

Rare is the man who chooses a woman and forever after has nary a lustful thought about any other. I think if a man had greater latitude to tell the woman that he loves that “yeah I still get that twitch in my pants for some new nookie but my love for you is much more important”, it would go a long way towards making relations between men and women a lot more honest.