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Why a Lot of Marriages Could Use a Third

... but it requires trust, honesty, and hard work.

Key points

  • One single person can’t possibly fill and meet all your needs.
  • We need something or someone to fill missing needs.
  • That someone or something who is not our partner is called The Third.
  • You can use The Third in a generative way or in a destructive way. It is up to you.
 Jessica Felicio/Unsplash
Source: Jessica Felicio/Unsplash

I was 29 years old and taking part in a three-day theater workshop. With me was a beautiful, married Italian theater teacher 20 years older than me. As a single looking for love in all the wrong places, I tried to woo her. For three whole days, I flirted and tried to seduce her. It didn’t work. As the workshop came to a close, she turned to me and said: “You’re really a wonderful man. I could easily fall in love with you. But I am married. I fall in love twice a week and take all that energy and channel it into my marriage.”

She said goodbye, walked away, and I never saw her again.

Twenty years later, I now understand what she meant. She was harnessing the power of The Third in her relationship.

What is "The Third"?

It is an illusion to expect our partner to fill all of our needs, fantasies, and desires. We all yearn to find our soul mate, the one, but even then they always fall short. One single person can’t possibly fill and meet all our needs all the time.

We have three options for dealing with our partners' shortcomings:

  • Give up on those unmet needs. Giving up on our needs over time leads to resentment, bitterness, numbness, or boredom.
  • Force our partner to fill those needs. Force them to take us out to that Michelin restaurant and hear them complain about the prices. Or roll their eyes as you go on and on about why the bass track of Taxman is legendary.
  • Outsource. Fulfilling needs and desires elsewhere. Find a (secret) someone with whom to fill those needs. A special friend, a friendly stranger, a bored neighbor, a flirty colleague….

That someone (or something) who is not our partner is called The Third.

The Third is any person or thing we desire that lies outside of the dyad. The obvious third could be a person, a lover. But it could also be your job, money, a marathon, hobby, art collection, or even your children. Family therapist Carl Whitaker notably stated that the most common “affair” is that of a mother with her children—affair in this case meaning displacing your libido (your life force) outside of your partnership. Under that definition, we all have multiple affairs all the time.

Much is written about sexual and romantic affairs. But there are many other types of Thirds.

Is the Third always bad?

The short answer is no. Losing yourself to a Third can lead to betrayal and potentially crossing boundaries of your bond, thereby hurting (and possibly ending) your relationship.

But cultivating a healthy and open relationship with The Third also has the potential to breathe new life into long-term committed relationships. It helps us feel seen, special, wanted, and energized. It allows our partner to seem less taken for granted, and therefore more desirable to us.

You can use The Third in a generative way (much like that theater teacher showed me 20 years ago) or in a destructive way; it is up to you.

“The presence of The Third is a fact of life; how we deal with it is up to us,” says family therapist Ester Perel.

How to incorporate the Third generatively

The short answer is it takes transparency, trust, play, and hard work.

  • Invest in your partner. Fill your partner’s love tank, and make sure they feel seen, heard, appreciated, and loved. Go towards their emotional bids. Make sure they feel confident in your love and commitment to them. This will ensure that you both are in love surplus and reduce feelings of insecurity and jealousy. Having such a strong base will help you integrate Thirds easily.
  • Identify your current Thirds. Reflect on and identify where is your libido, excitement, and vitality are currently directed. Remember, these features have intensities that can be modulated, just like a volume dial on your stereo—sometimes they're higher and sometimes lower. Share your findings playfully with your partner. As Perel reminds us: “Couples who feel free to talk honestly about their desires, even when they are not directed at each other, paradoxically become closer.”
  • Communicate with the Third. As you both slowly find Thirds to fill your identified needs (a book club, a therapist, a trusted friend who loves to talk about art), share them proactively with your partner. Don’t wait for them to ask about possible Thirds. Such updates build trust, a crucial component when integrating The Third in your relationship.
  • Enjoy the Third. When you are prioritizing your CrossFit class over your partner or going with your friends to that concert instead of date night, enjoy yourself. Just like that theater teacher told me: Fall in Love. Remember that you’re not actually falling in love with something or someone else; you’re falling in love with a part of yourself. You are bringing to life a part of you that revitalizes your world. The more parts of yourself you express and experience, the richer and more fulfilling life you’ll have.
  • Blast it back to your relationship. Take all the excitement, vitality, joy, play, exuberance, and energy you get from The Third, and channel it right back into your relationship. Return home with love, gratitude, and appreciation for your partner with renewed vigor. Show them that embracing The Third is a win-win for both of you.

You can’t control what or who your heart desires. You can control how you will act on those desires. Instead of fearing it, lean into it. It might seem counter-intuitive, but embracing The Third in an open and loving manner is one of the best ways to maintain a deep, vital, growing relationship.

Facebook image: Drazen Zigic/Shutterstock


Neill, J. R., & Kniskern, D. P. (Eds.). (1989). From psyche to system: The evolving therapy of Carl Whitaker. New York, NY: Guilford Press.

Perel, E. (2007). Mating in captivity: Unlocking erotic intelligence. New York, NY: Harper.

Perel, E. (2017). The state of affairs: Rethinking infidelity-A book for anyone who has ever loved. New York, NY: Harper.

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