“Wow. So that’s it, I guess, after a year of working together. I proposed a change in our working relationship, and she’s just gone. “I wish you well,” she says. “I can tell I won’t be able to satisfy you.” She never acknowledged the proposal. She called it my attack against her. She looks at me as though I’m nuts. Whatever rapport we had is vaporized — and the things she’s telling our colleagues? Wow.”

A rocket leaving Earth needs to reach escape velocity to tear itself away from our planet’s gravitational field. A molecule must be stimulated with the energy of activation before it is agitated enough to break free from other molecules. Similarly, in relationships — working teams, business partnerships, friendships, romances — when it’s time to call it quits, we all need a little oomph to overcome our inertia and get out the door.

How much we need depends on a lot of factors. Of course, there’s how strong the bond is: The longer you have been in a relationship, the more tentacles of collaboration there are to untangle, the harder it is to leave, and the more energy of activation is required.

Mind Readers Dictionary: The Podfast : Play in Popup

Mind Readers Dictionary : Play in Popup

Another factor is where you’re leaving to — what economists refer to as your opportunity costs, or what negotiators call your BATNA (best alternative to a negotiated agreement). If you’ve just won the lottery, it’s easy to say, “Take this job and shove it.” It’s harder if panhandling is your only alternative income source.

So, what supplies our energy of activation? What’s the fuel? Mostly, it’s the story we tell about how the relationship worked — or didn’t — and why we’re moving on.

Want serious thrust? Tell a story about how your partner was evil, mentally ill, congenitally deficient, or tragically flawed. Of course, some people are, but not as many as their departing partners tar as such. To listen to the recently relocated, you’d think the world is populated by twisted mutants.

Can’t bad-mouth your former partner? Well, that highlights another factor in the energy-of-activation equation: our capacity for self-deceptability.

Some people have extraordinary powers of self-deceptability; once they’re ready to go, they can tell any story that fuels their departure. With vast reserves of self-deceptability, they don’t feel any need to conserve. If faced with a choice between compromising and vilifying, they’ll take the latter — no speed bumps to worry about. They’re true believers who can turn on a dime — and turn on you, too. They own a supercharged getaway car on 24-hour dispatch.

Our departures are fueled by peer support, too — when we lobby friends to endorse our decision to go. We recruit peer support with the stories we tell. (But then we all tend to accumulate supportive peers anyway.) If we spin our stories with enough conviction, we can send a signal that we don’t want them questioned. Masters of self-deception know this, and so they tell their stories with great certainty and an air of feigned neutrality. They use whatever rhetoric it takes to spin their departure so it flies under the radar of anyone’s challenge: “My poor former partner, God bless her, I just didn’t realize how fundamentally damaged she is . . .”

Now, if your weak powers of self-deceptability aren’t up to the challenge of recasting your former ally as a cardboard cutout of a fool, that’s going to limit your ability to leave gracefully. You’ll end up more torn about whether to leave, more contemplative about what went wrong, and more concerned about whether there’s something for you to learn from it.

If you are handicapped by limited powers of self-deceptability, you will have to compensate, chiefly by taking great care in choosing partners. You’ll be OK if you partner up with people as self-deceptability impaired as you are, but partnering with the self-deceptability abled is high risk. When it comes to character assassinations, they’re much quicker on the draw than you’ll ever be, and they’ll have a first-out advantage in tarring you simplistically. Better to let them partner with each other.

How can you tell whether you’re dealing with someone with vast reserves of self-deceptability? The key is their capacity to believe uncompromising black-and-white stories on any subject, but especially about partners. Listen for the telltale binary sound: “You’re wonderful. My last partner was horrible. I’m neutral.” As they’re telling you about your unfortunate predecessor, chant to yourself the following mantra: “That’ll be me in due time. That’ll be me in due time . . .” And don’t be distracted by their high opinion of you. As long as you’re their friend, you’re fine. You’re more than fine — by their binary standard, you’re a saint. But it gets treacherous when the story flips, and it can flip quickly.