I've been dating this really great woman for three months. She's just decided that she needs to be single right now, despite our forming a pretty strong connection. She explained that she really, really likes me, but she's never been single for very long and thinks it's best for her at the moment. I can respect that. She also says we can keep sleeping together if I want. I want to do that, but I'm wondering: Could that ruin our chances of having a real relationship again in the future?

--Wanna Play It Smart

People give you a reason for their behavior. It may not be the real reason. Like, I'd tell somebody, "So sorry...got a work thing!" and not, "I'd shave off my eyebrows to get out of your 8-year-old's oboe recital."

There's a good chance you've been demoted from boyfriend to emergency penis. Research by evolutionary psychologist Joshua Duntley suggests that we evolved to cultivate backup mates -- plan B partners we can quickly pivot to in case a partner ditches us or dies in a freak accident. Many or most of us seem to have a backup mate or two -- somebody we flirt with regularly or otherwise set up as our romantic fallback, though we aren't always consciously aware of it.

Maybe you're all, "Hey, fine by me if she wants to keep me as her sexual service department while she's shopping around." Maybe you're hoping she'll find other dudes lame in comparison. Totally possible. But if what really matters to you is having a relationship with her, all that availability on your part is not a good look. The problem is "the scarcity principle." Psychologist Robert Cialdini explains that we value what's scarce or out of reach, fearing that we'll lose access to it. In fact, the desirability of the very same person or thing often increases or decreases according to shifts in its perceived accessibility. (Picture Denny's with a velvet rope and a scary bouncer instead of "Open 24 hours! Seat yourself!")

Once your value is perceived to be low, there might not be much chance of rehabbing it. So it might pay to find other sex partners and give this woman a chance to miss you. It ultimately serves your purpose better than turning yourself into the man version of those freeze-dried food packs sold for earthquake or apocalypse prep kits: delicious like seasoned particle board but just the thing while you're waiting for rescue in the remains of your office building with nothing to eat but your arm.

For pages and pages of "science-help" from me, buy my latest book, "Unf*ckology: A Field Guide to Living with Guts and Confidence." It lays out the PROCESS of transforming to live w/confidence.