The Role of Love in Interpersonal Relationships

Love is one of the most studied yet still deeply nuanced forces in human psychology. It shapes how we connect with others, how we see ourselves, and how deeply we invest in our most important relationships. While poets have long tried to define it, psychologists have worked to break it down into measurable, meaningful components. One framework that has stood the test of time is Robert Sternberg’s Triangular Theory of Love, which proposes that love is not a single feeling but a dynamic interplay of three core elements: passion, intimacy, and commitment. Understanding how these elements work – and how they shape relationship satisfaction and personal well-being – gives us a far clearer picture of what love actually does in our lives.

What is love, really? 🔗

In everyday language, “love” is used to describe everything from how someone feels about a partner to how they feel about their morning coffee. In psychology, the definition is more precise. Love in the context of interpersonal relationships refers to a set of emotional, motivational, and cognitive experiences that bind people together over time. It is not just attraction or affection – it involves a sense of closeness, a desire for the other’s well-being, and often a decision to stay.

Love also plays a direct role in psychological health. Research in relationship psychology consistently finds that positive self-esteem – our sense of worth as a person – is closely tied to the quality of our loving relationships. When we feel genuinely valued and cared for, we begin to internalize that sense of worth. This, in turn, builds confidence in our ability to navigate challenges, a quality known as self-efficacy. In short, being loved well helps us believe in ourselves.

A large-scale meta-analysis published in the Journal of Personality and Social Psychology confirmed that the relationship between social connections and self-esteem is genuinely reciprocal across all stages of life, functioning as a positive feedback loop between the two constructs. Better relationships build stronger self-esteem, and stronger self-esteem helps us maintain better relationships.

Sternberg’s triangular theory of love 🔗

Psychologist Robert Sternberg first introduced his triangular theory in a landmark 1986 paper in Psychological Review. According to the theory, love has three components: an intimacy component, a passion component, and a commitment/decision component. Intimacy refers to feelings of closeness, connectedness, and bondedness; passion encompasses the drives leading to romance, physical attraction, and sexual consummation; and commitment refers, in the short term, to the decision that one loves another, and in the long term, to the commitment to maintain that love.

What makes this theory particularly useful is not just its description of these three elements in isolation, but how it explains the combinations they form. These three components interact to produce eight types of love: nonlove, liking, infatuated love, empty love, romantic love, companionate love, fatuous love, and consummate love. Each represents a different configuration of what is present and what is missing in a relationship.

Passion: the motivational force 🔗

Passion refers to the drives that lead to romance, physical attraction, sexual consummation, and related phenomena. It includes motivational and other forms of arousal that produce the experience of passion in a loving relationship. Passion tends to be the most immediately felt component – it is what draws people toward each other in the early stages of a relationship. However, it is also the most volatile. Research suggests that passion can diminish over time as familiarity grows, though it remains a significant predictor of relationship satisfaction, particularly in younger romantic relationships.

Intimacy: the emotional core 🔗

Intimacy is often described as the “warm” component of love. It is built through shared experiences, vulnerability, honest communication, and mutual support. The intimacy component forms a common core in loving relationships – it appears across love for a mother, father, sibling, best friend, or romantic partner, whereas passion and commitment tend to be experienced more selectively.

A 2024 study on long-distance relationships found that intimacy, along with passion and commitment, predicted relationship satisfaction – with intimacy being the most influential factor of the three. This reinforces what many couples discover over time: emotional closeness tends to be the foundation that holds everything else together.

Commitment: the deliberate choice 🔗

Commitment is the cognitive and volitional dimension of love. In the short term, it refers to the decision that one loves a certain other; in the long term, it refers to one’s commitment to maintain that love. Importantly, one can be committed without feeling the other two components, and one can feel passion and intimacy without commitment.

Research confirms that commitment itself is a key predictor of relationship longevity. However, commitment alone – without intimacy or passion – produces what Sternberg calls empty love: a relationship that may technically persist but feels hollow to both partners.

The eight types of love 🔗

One of the most practical aspects of Sternberg’s theory is its taxonomy of love types, each defined by the presence or absence of its three components. Understanding these can help individuals recognize where their own relationships stand – and what might be missing.

Liking involves intimacy alone – the closeness of a good friendship with no romantic pull. Infatuated love is passion alone, intense but unstable, with no real closeness or commitment behind it. Empty love consists of commitment without warmth or desire. Romantic love combines passion and intimacy but lacks long-term commitment. Companionate love blends intimacy and commitment – the deep bond of long-term partners who may have lost the early spark. Fatuous love pairs passion and commitment without emotional closeness, often seen in whirlwind relationships that move too fast. And consummate love – the integration of all three components – is what most people are working toward.

According to Sternberg, relationships tend to be more successful when partners’ triangles match – when each person is seeking more or less the same thing from the relationship. Compatibility in what love means to each partner is a crucial factor in whether relationships endure.

Consummate love: the complete form 🔗

Consummate love is the complete form in the model and is theorized to be associated with the “perfect couple.” According to Sternberg, these couples maintain sexual intimacy long into the relationship, cannot imagine being happier with anyone else, overcome difficulties gracefully, and take delight in each other. However, Sternberg cautions that maintaining consummate love may be even harder than achieving it, stressing that without expression, even the greatest of loves can die.

This last point is essential. Consummate love is not a static destination – it requires ongoing investment. Research indicates that stronger commitment often stems from greater relationship satisfaction, which couples can cultivate through intimacy, support, quality time, and appreciation. Love, in its most complete form, is an active practice, not a passive state.

How love shapes self-esteem and self-efficacy 🔗

Beyond the dynamics of the relationship itself, love has a measurable impact on the individuals within it. Research on couples shows that support providers with higher self-esteem experienced greater efficacy during couples’ support discussions and delivered greater support to their partner, which in turn led the recipient to experience greater efficacy and higher self-esteem over time.

This finding points to something important: love in a healthy relationship is not just emotionally fulfilling – it is developmentally powerful. When a partner consistently supports, affirms, and encourages us, we become more capable, more confident, and more willing to take on challenges. Research published in Nature Reviews Psychology proposes that self-esteem is best understood as influencing relationships indirectly through a causal chain of mechanisms including trust and reciprocated behaviors between partners, which ultimately affects each partner’s satisfaction with the relationship.

At the same time, low self-esteem can create real barriers in relationships. Individuals with low self-esteem may engage in indirect support-seeking behaviors – such as sulking or displaying sadness – to elicit care from a partner. Research shows that when such behaviors occur, partners tend to respond with less support, meaning that the very strategy used to seek closeness actively drives it away. This dynamic illustrates why personal psychological health and relational health are deeply intertwined.

How love changes across relationship stages 🔗

Love is not static. Its composition shifts as a relationship develops. Research shows that while the influence of passion and intimacy on relationship satisfaction grows across relationship stages, the influence of commitment actually decreases over time – suggesting that as couples develop deeper bonds, the felt experience of connection matters more than the initial decision to stay together.

As relationships progress, habituation and reduced novelty may diminish initial passion. However, intimacy tends to grow with time and shared experiences. This shift is not necessarily a sign of decline – it may reflect a healthy transition from the intense early phase of love toward a deeper, more stable form. Understanding Sternberg’s framework helps couples contextualize these changes rather than interpret them as failure.

Applying the theory: what it means for real relationships 🔗

Sternberg’s theory is not just academically interesting – it is practically useful. The primary goal of applying the triangular theory is to allow a therapist or individual in a relationship to identify where one of the components is absent or weak, and take some action to strengthen it, thereby improving or better understanding the relationship.

For instance, a couple who share deep commitment and emotional intimacy but feel their passion has faded can recognize they are experiencing companionate love – and actively work to reintroduce the novelty and physical connection that rekindles passion. Similarly, a relationship that feels emotionally intense but lacks any real commitment can be recognized as romantic love, prompting a conversation about where the relationship is headed.

Positive self-esteem is critical to an individual’s mental health and ability to relate well to others. Strengthening self-esteem increases contentment in relationships and, as a result, the emotional health of all involved. In practical terms, this means that individual psychological work – building self-worth, developing emotional regulation, and learning to communicate effectively – directly feeds the health of the relationships we are part of.

What do you think? Looking at Sternberg’s three components – passion, intimacy, and commitment – which do you think is hardest to sustain over the long term, and why? And in what ways do you think a loving relationship has shaped how you see your own capabilities?

References

1. https://www.robertjsternberg.com/love
2. https://www.psychologytoday.com/us/blog/in-it-together/201801/building-self-esteem-and-improving-relationships
3. https://pubmed.ncbi.nlm.nih.gov/31556680/
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC10001731/
5. https://www.nature.com/articles/s44159-023-00247-z
6. https://www.psychologytoday.com/us/blog/overcoming-destructive-anger/202406/how-low-self-esteem-can-impact-an-intimate-relationship
7. https://www.simplypsychology.org/types-of-love-we-experience.html