THE BLOG
06/23/2014 04:35 pm ET | Updated Aug 23, 2014

When Is a Deal Breaker Not a Deal Breaker?

Rick Gomez via Getty Images

Many years ago -- long before I met and married my husband -- a guy I was dating regaled me with a story of how his cat ate his father's dentures one holiday weekend. His dad had to go toothless for days till his dentist opened up again. "I'll be more careful with mine," my beau assured me.

"Um... what?"

My date shrugged and gave me a grin with his clearly natural set of choppers. "Our teeth go south on us in my family, so I'll have them all pulled at some point, like my dad did."

To which I responded with something I'm not proud of, but stand behind to this day: "You can't have them pulled. You have to have teeth."

And there it was: my relationship deal breaker.

Everybody has one -- usually several. Maybe yours isn't teeth. Maybe it's politics. Or body hair. Maybe it's the fact that no matter how many times you tell him, he still pretends that he has no idea what happened to the last of the toilet paper when you once again screech from the bathroom that you cannot wipe with a cardboard tube.

But here's the strange, fluid thing about deal breakers: They are like Schrödinger's cat. They both are and are not absolute.

By definition, deal breakers are those areas on which you cannot compromise in a relationship -- i.e., I will never be able to have a long-term relationship with a toothless man -- at least not until we're pushing 80 or so. (Don't judge me.)

But a friend of mine -- a woman who, as she approached her mid-thirties, realized she wanted children -- fell in love with a man who had no desire at all for a family.

"I knew that if I married him, then kids were out of the question," she told me after he proposed. "And that was almost a deal breaker. But he doesn't want kids much more than I do want them. And I want a life with him more than I want children." They married, and for nearly a decade since, they have been contagiously happy.

There's a difference between a true core deal breaker -- one that will cause trouble down the road if you ignore it -- and something you think is a deal breaker until you meet the person who renders that thing far less important than you thought.

Here are some questions to ask yourself to figure out which one you're facing:

• Is it superficial or intrinsic?

Is the "deal breaker" really more of a pet peeve, or is it something basic to your nature -- bad grammar versus bad money management, for instance? A woman I know thought she could accept her husband's heavy drinking -- until they had children, when the deal breaker it had truly been all along for her was no longer tenable. Deep-seated, fundamental deal breakers are like a scabbed wound that never heals, and years of picking at them will wear away at the foundation of your connection.

• Does it have to do with your safety and physical and/or mental well-being?
Verbal and physical abuse is always -- always -- a deal breaker.

• Is the deal breaker something that's antithetical to your lifestyle?
I knew a man who asked a woman he was very interested in for a date to his favorite place: a sports bar with the best beer and wings in town. As soon as she arrived, he knew they wouldn't get past the first date: she'd biked there, told him she hated sports and, as an herbalist vegan, ordered hot tea and plain salad. He had nothing against her choices, but he said he knew right away that they'd have a hard time finding common interests and activities.

• Is it an ingrained idea or prejudice you formed when younger and have never reexamined?
A close friend used to tell me, "I'd never date a musician." Guess who she's engaged to now?

There's a difference between reevaluating a deal breaker and settling. Knowing which is which can be a tricky proposition. I thought that energy level was a deal breaker for me -- as in, I generally have the energy level of a jackrabbit on Adderall, and I knew I couldn't be with anyone who didn't. Yet my husband is an introvert, a quiet type, a man whose idea of the perfect day off is to sit on the sofa and watch movies. All. Day. Long.

Not a deal breaker, it turns out -- because he's also funny, and kind, and smart, and genuine, and loving, all qualities that far outweighed what I'd thought was a rigid criterion.

Oh, and most important -- he has teeth.

Phoebe Fox is the author of The Breakup Doctor series, from Henery Press.