The 3 Things Every Relationship Needs to Last, According to a Psychologist

The post The 3 Things Every Relationship Needs to Last, According to a Psychologist first appeared on Crafting Your Home.

Relationships can be surprisingly easy to overcomplicate.

Attachment styles to analyze, compatibility tests to take, and countless rules about what couples supposedly need to do to stay together. But psychologist Robert Sternberg proposed a much simpler way of looking at romantic relationships nearly four decades ago.

His Triangular Theory of Love says romantic love has three central components: intimacy, passion, and commitment.

A 2026 scoping review examining 27 studies revisited Sternberg’s theory and found that these three components continued to appear across different cultures and relationship types.

That doesn’t mean every relationship needs an identical balance of all three. Sternberg’s framework specifically recognizes that people’s expectations for relationships differ.

But it does offer an interesting way to think about what may be happening inside a relationship.

Intimacy

A loving couple embraces while sleeping peacefully in a cozy bed setting. — Image Credit : cottonbro studio / Pexels

Intimacy is about feeling genuinely close to another person.

It’s the sense that your partner knows you, understands you, and is someone you can rely on. Sternberg describes it as closeness, connectedness, and bondedness, with friendship, trust, communication, and caring all playing a role.

Intimacy doesn’t necessarily come from dramatic romantic gestures.

It can appear in ordinary moments.

Your partner remembers something important you mentioned weeks ago. They know when you’ve had a difficult day. They listen when you’re frustrated rather than immediately trying to solve the problem. They make time for you when life becomes busy.

Those small interactions can create the feeling that you’re not simply sharing a life with someone but actually being known by them.

Strong intimacy also involves sharing your own inner world.

Talking about hopes, worries, frustrations, and what excites you gives your partner opportunities to understand parts of you that aren’t visible during everyday routines.

Passion

Passion is the part of Sternberg’s triangle associated with the pull between two people.

It can include sexual attraction, but the theory doesn’t define passion as sex alone. Sternberg describes it more broadly as a strong desire to connect with another person.

Passion doesn’t necessarily stay at the same level throughout a relationship.

The intensity of a new romance can change as couples become more familiar with each other and everyday responsibilities take over.

That doesn’t automatically mean the relationship is failing.

Long-term relationships can have periods when passion is particularly strong and other periods when intimacy or companionship takes priority. A 2026 discussion of Sternberg’s theory similarly emphasizes that the triangle can change shape over time rather than remaining fixed.

For couples, the useful question isn’t necessarily whether passion looks exactly as it did at the beginning.

It may be whether both people still value the romantic connection they share and whether they want to make room for it.

Commitment

Commitment is the decision to love someone and the ongoing decision to maintain that relationship.

It can be obvious in marriage or other long-term arrangements, but it doesn’t require one particular relationship structure. Sternberg’s framework treats commitment as something that depends partly on the agreements and expectations the people involved share.

Commitment can show up in everyday decisions.

You consider your partner when making plans. You discuss major decisions rather than making them entirely on your own. When the relationship encounters a difficult period, you don’t automatically treat the first problem as a reason to walk away.

That doesn’t mean commitment requires someone to remain in every relationship regardless of circumstances.

Instead, within a relationship that both people want to continue, commitment provides a sense of direction.

It answers a basic question: Are we choosing to build something together?

The Three Don’t Have to Be Equal

This may be the most important part of the theory.

Sternberg doesn’t argue that every relationship needs the same amount of intimacy, passion, and commitment at every moment. In fact, the balance can change as relationships develop.

A couple dealing with an exhausting period of life may temporarily rely more heavily on commitment and emotional closeness.

At another point, romance and passion might take center stage.

That’s normal.

Trying to measure your relationship against an imaginary perfect triangle could create unnecessary pressure. The theory is better understood as a framework for thinking about what you and your partner actually want.

What If Partners Want Different Things?

The triangle becomes especially interesting when two people experience the same relationship differently.

One partner might place enormous importance on emotional closeness, while the other emphasizes passion. One might already see the relationship as a long-term commitment while the other isn’t sure about the future.

Neither person is necessarily wrong.

But the difference can become important if they aren’t aware of it or never discuss it.

Recent coverage of Sternberg’s theory describes the value of comparing the relationship each person actually has with the relationship they ideally want. When those expectations differ significantly, assuming everything will eventually sort itself out may not address the underlying mismatch.

That makes honest conversations particularly valuable.

Your Relationship Doesn’t Need a Perfect Formula

It’s tempting to turn relationship advice into another checklist.

Do this much. Communicate this often. Have this much passion. Never argue. Always make time for romance.

Real relationships are rarely that tidy.

Sternberg’s theory is useful partly because it doesn’t insist on one perfect version of love. His framework recognizes that people want different things from relationships and that those wants can change over time.

Instead of asking whether your relationship looks like someone else’s, it may be more useful to ask three questions:

Do we feel genuinely close?

Is there still a romantic or passionate connection that matters to both of us?

Are we both committed to the relationship we’re building?

The answers don’t have to be perfect.

But they can reveal where a couple feels strong, where something has changed, and where a conversation might be worth having.

After all, lasting love probably isn’t about maintaining one perfect balance forever.

It’s about understanding what the relationship needs as the two people in it keep changing.