Your Relationship Needs These 3 Things to Last—Does Yours Have Them?

The Triangular Theory of Love, Explained

What does it mean to love someone? Is it an out-of-the-blue text that compares thee to a summer’s day, or matching holiday snuggies? Is it tolerating their passive-aggressive parents, or choosing them even when you’re mad as heck at them? That’s the question psychologist Robert Sternberg set out to answer four decades ago with his still-relevant “Triangular Theory of Love.”

Created by Sternberg in 1986, the triangular theory of love proposes that there are three core components of love: Intimacy, passion, and commitment. The presence (or absence) and intensity (or lack thereof) of each of these ingredients influences the “type” of that relationship—as well as how satisfying that love may feel for the people involved.

Put simply, different combinations make for different types of love. Intimacy with minimal commitment or passion, for example, might look more like friendship, while relationships characterized only by commitment are generally considered empty. Further, relationships marked primarily by passion (a.k.a. infatuated love) generally fizzle as quickly as they begin.

As you might have guessed, many people strive for relationships that have all three components—a combination Sternberg calls “consummate love.” And for many, having all three may feel happy, healthy, and fulfilling. However, the triangular theory of love is not meant to be prescriptive. As Sternberg tells Cosmopolitan, “Each person's ideal is different. There is no one ideal that works for everyone.”

But while it doesn't offer a simple recipe for Relationship Success™, the framework can give you fodder for figuring out what you have, what you want, and where the two might not quite match in your current close relationships.

Intimacy, passion, and commitment are three words whose definitions can vary from person to person and culture to culture. So, I asked the man who created the theory himself to define them:

Intimacy: In the context of the triangle, intimacy refers to feelings of closeness, bondedness, and connectedness, explains Sternberg. “It's friendship, caring, trust, and communication, too,” he says.

In practice, this can manifest as having high regard for that person, reflected in how you talk or think about them, as well as feeling you can count on them (and being someone they can count on, too).

It can also show up as a desire to support another’s well-being—by helping them make doctor appointments, refilling their water glass, or showing up with takeout after a week from hell, for instance. Sharing your inner world, possessions, time, and energy with someone can build intimacy, too.

Passion: Sternberg says that in the context of his theory, passion is “the feeling that you cannot live without someone.” It's when “you cannot get the partner or potential partner off your mind, and that somehow that person is just absolutely necessary for your happiness,” he says.

Yes, passion can be marked by a thrum of sexual desire. But “while passion can be sexual, it need not be,” Sternberg tells Cosmopolitan. Other needs—including those for nurturance, affiliation, dominance, submission, and self-actualization—can contribute to the experience of passion, according to the theory. Meaning, passion isn’t just a polite reframe of horniness; it refers to the pull you feel toward another person that makes you want (nay, crave!) to be connected to them.

Commitment: Sometimes called the decision vertex, the commitment component of love consists of two aspects: The decision to love someone, and the commitment to maintain that love, explains Sternberg.

Obviously, this is sometimes marked by a ring on your left hand, a shared lease, a co-parenting agreement, or a shared Costco membership. But it can also mean factoring someone into decisions about your future or choosing to work through conflict rather than getting out of dodge.

Commitment may not have the same sex appeal as the other legs of the triangle, but Sternberg’s theory suggests it does some serious heavy lifting. “This component can be essential for getting through hard times and for returning to better ones,” he writes in the originally published theory.

FYI: Commitment isn’t synonymous with monogamy, according to Sternberg. Because commitment can look different in different relationships, based on their unique structure and agreements, what matters most is that both (or all) partners agree on what commitment means. “If one partner sees commitment as monogamous, and the other sees it as polyamorous, there are likely to be problems,” Sternberg says.

The Happy Relationship Formulas

The Triangular Theory of Love cannot tell you exactly what ratio of intimacy, passion, and commitment will guarantee happily-ever-after. Sternberg says there is no single perfect triangle to strive for because what people want from their relationships varies. Still, there are a few triangle formations that may bode well for the lovers involved, he says.

1. Matching Triangles: “When two partners have nearly matching triangles,” Sternberg says. “This suggests that they want the same things out of the relationship.” If you’re looking for a relationship that’s heavy on intimacy and commitment, while your partner is primarily interested in passion, that mismatch may eventually make itself known.

2. Big Triangles: In Sternberg's model, the size of the triangle approximates the amount of love experienced. When the triangles are larger for everyone in the relationship, he says, it generally means there is lots of the tender, loving, caring good stuff present in the relationship.

3. Ideal-Match Triangles: Finally, relationships tend to feel good for the people involved when “one’s actual triangle for the partner is close to one's ideal triangle for the relationship,” says Sternberg. In other words, “what one has is close to what one ideally wants,” he says.

The Triangle Is Supposed to Shape-Shift

Before you start panic-measuring your current relationship(s) against the arms of a hypothetical triangle, know this: “You do not need to maintain equal quantities of intimacy, passion, and commitment at any or every moment,” says certified sex therapist Heather McPherson LPC-S, LMFT-S, CST-S, the CEO and Founder of Sexual Health Alliance, a professional training network for sexuality professionals. In fact, fluctuation is baked into Sternberg’s theory: He proposes that in long-term, loving partnership, intimacy and commitment tend to play larger roles, while passion may decline somewhat over time.

All relationships have seasons—and your triangle may shape-shift along with them, says McPherson. “There are periods when commitment carries you through exhaustion, loss, or a new addition to the family, and then there are periods of intense eroticism when intimacy hasn't caught up yet,” she says. Other periods may be especially rich in companionship and emotional closeness.

Rather than treating those changes as evidence that something is wrong, expect some ebb and flow. “Remembering and acknowledging these ups and downs can bring comfort and flexibility to the relationship,” says McPherson, including when one side of your triangle feels a little less robust than you’d like.

How to Strengthen Your Relationship

Don’t stress if you’ve assessed your current relationship against the Triangular Theory of love and feel like it's falling short. Instead, treat your initial assessment of your relationship triangle as an invitation to get curious—about your own wants and experiences in the relationship, and your partner’s.

“Ask yourself and your partner open-ended questions about things you haven't asked in a while,” says McPherson. Her suggestions:

• What has been happening inside you lately that I don't know about?
• When do you feel most understood by me?
• What areas of life do you feel alone in?

Alternatively, you both can hop on the Organized Conversation bandwagon and invest in Where Shall We Begin? or Table Topics Date Night.

“Intimacy grows through attention, vulnerability, responsiveness, and the experience of being known,” says McPherson. So, simply asking—and answering—questions like these may help nurture that side of your triangle, she says.

If commitment is feeling like the flimsy side of your triangle, a heart-to-heart with your partner about what it means to each of you can help, says McPherson. “Commitment becomes stronger when it is explicit rather than assumed,” she says. So, rather than assuming you share the same definition, she suggests asking:

• What are we building?
• What are we protecting?
• What are we willing to work through?
• What are our agreements?
• What would make you feel more secure in this relationship?

And if passion is the piece that you’re missing, McPherson suggests being more intentional about cultivating it. “Sometimes passion needs more attention, focus, and time spent cultivating it,” she says. (Hey, don’t knock scheduled intimacy until you’ve tried it). Conversely, passion may also need a little extra breathing room. “Desire often requires the experience of the other person as a separate person, not simply as your roommate or co-parent.”

So, the Triangular Theory of Love can offer a fun, helpful framework for thinking about your current and/or ideal relationship. But “turning the triangle into another relationship performance metric is usually not helpful,” says McPherson. Instead, if you've got a partner, use the theory as conversation fodder because talking about your triangle—and relationship more broadly—can actually strengthen and expand it, she says.