Dear Emily,

To add spice to our sex life, my wife and I act out certain fantasies. A favorite is when we imagine we’re old friends married to other people. We are passengers on a flight that is diverted to an island due to a raging storm. We share a room for the night in a modest beach hotel, and to ease her anxiety, I comfort her by getting very intimate and making love to her.

In our sex fantasies, we are always not married to each other. Recently, she suggested we fantasize having sex with someone else. I asked her who she would be thinking of—her crushes Brad or Tom—both of which I would have played along.

But when she said “secret,” I suspected she’d imagine sex that night with her first suitor, and most probably on many other nights. She has been talking a lot about him since he appeared in the papers after his promotion to president of his company.

He courted her when he was only a lowly engineer in the company and dropped out of the scene when he realized there was a big gap between their economic standing. She sounded like she rued losing him.

Could her fantasies lead her to actually have sex with him and, ultimately, have an affair? Should I be concerned about it? What can I do to stop her from fantasizing about him?

—ARCHIE

Weren’t you privy to this playacting from the start? What’s making you suddenly insecure about her fantasies? Is your mind on overdrive fantasizing over her fantasies?

Be concerned when she starts calling out his name while she’s in deep sleep, or in the middle of an intimate moment with you.

But, unless she makes an effort to reach out to him through friends with empathetic fillers, allow her mind to whirl free and fantasize a life of what-could-have-been with him, had fate not intervened.

You cannot stop her from thinking thoughts she wants, as there is no contraption yet invented that can rein in runaway minds. It can’t be shackled, put in a corner, or hooded over. It is the only thing in the world that can run free, fly and roam unimpeded.

Best to talk with her about your worries. You might still learn something you never knew about her. And play yourselves instead of assuming other people’s identities in your fantasy games. It’s safer.

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