The fascinating new Showtime series Masters of Sex is based on the story of Bill Masters and Virginia Johnson, pioneers of research about human sexual behavior.

The truths of intimate relationships abound in this show. Here’s just one example.

The wife of the university provost, tired of being ignored, stumbles into her own affair. Recently dumped by her lover, she sits recovering at the bar and, by chance, strikes up a conversation with (unknowingly) her husband’s young male lover. Her husband walks in to meet the guy, and the truth silently reveals itself.

Allison Janney, who plays the provost’s wife, shined tonight with her pained plea to the young man:

Stay single.
I only say this to you because, when you’re young and in love, everyone thinks they’ll be the exception.
Sure, maybe Mom and Dad slept in separate beds and then separate rooms.
Maybe the older couples you know bicker or fight.
At your age, you can’t imagine it will ever be you
but it will be,
which is bad enough, but what’s even worse
is how much you’ll feel like a failure.
Because when the person who knows you best loses interest
that really takes something out of you
like surgery almost
and you really start to wonder
if you’ll ever be whole again.

Even those of us who don’t miss a single minute of those old relationships can identify.