Love Changes in Stages

Romantic relationships are not static; they undergo qualitative transformations over time. Understanding these changes is crucial for reframing the feeling that "the spark has died" not as the end of love, but as a transition to the next stage.

Robert Sternberg (1986)'s Triangular Theory of Love posits that love comprises three components - "Intimacy," "Passion," and "Commitment" - and that the combination of these elements shifts over time. In the early stages, passion dominates, but as time passes, intimacy and commitment tend to increase while passion decreases.

Helen Fisher (2004) mapped love onto three brain systems from a neuroscience perspective: (1) Lust: sexual desire driven by testosterone and estrogen. (2) Attraction/Romantic Love: intense fixation on a specific person, driven by dopamine and norepinephrine. (3) Attachment: long-term bonding driven by oxytocin and vasopressin. These systems can operate independently, but in healthy long-term relationships, all three become integrated.

This article integrates these theories to analyze which Big Five traits become important at each stage of romantic love.

Stage 1: The Passion Phase - When Extraversion and Openness Shine

The early stage of romance (roughly the first 6-18 months of dating) is when Fisher's "Attraction" system is most active. fMRI studies have confirmed that the brains of people in early-stage love show strong activation of the ventral tegmental area (VTA) and caudate nucleus, with massive dopamine release (Aron et al., 2005). This neurochemical state produces characteristic symptoms: intense fixation on the partner, idealization, increased energy, and reduced sleep.

The most important Big Five traits at this stage are extraversion and openness.

The role of extraversion: Initiating a relationship requires self-disclosure, proactive approach behavior, and social energy. Highly extraverted people excel at forming first impressions, leading conversations, and actively proposing date plans. Back et al. (2011) demonstrated that extraversion is the trait most strongly associated with attractiveness in "zero-acquaintance" situations.

The role of openness: A new relationship is "an adventure into unknown territory." People high in openness have strong curiosity toward new experiences, enjoy novel activities with a partner, and are eager to explore the relationship's possibilities. Openness also correlates with "depth of self-disclosure," and the ability to have deep conversations early on accelerates the development of intimacy.

However, the "passion" of this stage is neurochemically unsustainable. Marazziti et al. (1999) showed that the serotonin decrease characteristic of early love (which causes obsessive thinking) normalizes within 12-18 months. In other words, the "butterflies" of romance are biologically time-limited.

Stage 2: The Reality Phase - When Agreeableness and Conscientiousness Are Tested

Once the neurochemical "intoxication" of the passion phase wears off, the partner's realistic qualities become visible. The idealization filter is removed, and the other person's flaws and differing habits become noticeable. This stage (roughly 1-3 years into the relationship) is when many couples feel "this isn't what I expected" and waver about continuing.

Murray et al. (1996) described the process by which "Positive Illusions" formed in the early relationship are gradually corrected toward reality. When this correction is too abrupt, it becomes "disillusionment"; when gradual, it becomes "mature understanding."

The most important traits at this stage are agreeableness and conscientiousness.

The role of agreeableness: The reality phase is a period of increasing conflict. Differences in lifestyle habits, value mismatches, and expectation gaps surface. Highly agreeable people demonstrate the ability to handle these conflicts cooperatively and through compromise, maintaining relationship stability. McNulty (2008)'s longitudinal study confirmed that agreeableness plays a crucial role in maintaining relationship satisfaction during the newlywed period.

The role of conscientiousness: After passion fades, what sustains a relationship is "deliberate effort." Highly conscientious people keep promises, fulfill responsibilities, and continue investing in the relationship. Planning dates, remembering anniversaries, daily acts of consideration - these "relationship maintenance behaviors" are supported by conscientiousness. Jackson et al. (2014) showed that conscientiousness is one of the strongest predictors of long-term relationship stability.

Stage 3: The Maturity Phase - When Emotional Stability Becomes the Foundation

Couples who navigate the reality phase enter the maturity phase (3+ years together). At this stage, Fisher's "Attachment" system takes the lead, forming deep bonds based on oxytocin and vasopressin. Passion is no longer as intense as in the early days, but it doesn't disappear entirely - it persists as a "gentle warmth."

Acevedo & Aron (2009)'s fMRI study confirmed that even couples in long-term relationships (average 21 years) show VTA (reward system) activation when viewing their partner's photo. However, activation in brain regions associated with early-stage "obsessive fixation" decreased, replaced by activation in regions associated with "calm attachment." Related books can also be found at related books (Amazon).

The most important trait at this stage is emotional stability (low neuroticism).

The role of emotional stability: In long-term relationships, couples face life's various hardships together (illness, job loss, family problems, aging). Emotionally stable people can respond calmly to these stressors and serve as emotional anchors for their partners. Roberts et al. (2007)'s longitudinal study showed that emotional stability tends to naturally improve with age, which may be one reason why long-term relationship stability increases over time.

Additionally, in the maturity phase, balancing "personal growth" and "relationship maintenance" becomes important. Aron et al. (2013)'s self-expansion theory demonstrates that sharing new experiences with a partner contributes to relationship vitality even in long-term relationships. Here, openness becomes important again, playing a role in preventing "staleness."

Stage-Transition Crises and How to Overcome Them

Transitions between stages of love are often experienced as "crises" in the relationship. The transition from the passion phase to the reality phase, in particular, represents the first major trial for many couples.

Passion → Reality crisis: People feel that "the romance has cooled" or "there's no more excitement," leading to anxiety about whether "I don't love them anymore." However, this is a decline in passion, not the disappearance of love. Sprecher (1999)'s longitudinal study showed that passionate love decreases over time, but companionate love can increase. Understanding this transition as a "normal process" prevents unnecessary relationship termination.

Reality → Maturity crisis: Questions arise such as "Is it right to stay together?" or "Is there someone better suited for me?" This is explained by Rusbult (1983)'s Investment Model as a balance between "attractiveness of alternatives" and "investment size." The greater the investment in the relationship (time, emotions, shared experiences), the more one can resist the allure of alternatives.

Personality resources for overcoming crises: Openness provides the flexibility to "view relationship changes as growth opportunities." Conscientiousness provides the perseverance to "continue investing in the relationship during difficult times." Agreeableness provides the tolerance to "accept the partner's changes." And emotional stability provides the foundation to "remain calm in the face of crisis."

Knee et al. (2003) showed that people who hold "Growth Beliefs" - the belief that relationships can be improved through effort - navigate stage-transition crises more adaptively. This belief correlates positively with openness, while fixed "Destiny Beliefs" correlate positively with neuroticism.

Relationship Maintenance Strategies for Each Stage

Each stage of love has its own appropriate relationship maintenance strategies. Building on Stafford & Canary (1991)'s relationship maintenance theory, here are recommended strategies for each stage.

Passion phase strategies: The need for relationship maintenance is low at this stage, but building foundations for the future is important. (1) Create a foundation of intimacy through deep self-disclosure. (2) Build "a world for two" through shared activities. (3) Prepare to accept the partner's realistic qualities without becoming overly immersed in idealization.

Reality phase strategies: This stage requires the most maintenance. (1) Schedule regular "relationship check-ins" - dedicated time to openly discuss mutual satisfaction and dissatisfaction. (2) Consciously practice conflict resolution skills (Gottman's "repair attempts"). (3) Adjust the balance between individual time and couple time. (4) Make expressing gratitude a daily habit.

Maturity phase strategies: (1) Consciously incorporate new shared experiences to prevent staleness (Aron et al., 2000's "self-expansion activities"). (2) Support each other's personal growth, maintaining a relationship of "interdependence" rather than "codependence." (3) Consciously maintain physical intimacy (everyday contact like holding hands, hugging). (4) Reflect on the relationship's history, acknowledging shared hardships and growth.

Integrating Compatibility Assessment with Relationship Stages

When interpreting this site's compatibility assessment results, it's important to consider which stage the current relationship is in. Even with the same personality combination, "strengths" and "challenges" change depending on the stage.

For example, a couple where both partners are high in extraversion will build a very active and enjoyable relationship during the passion phase, but upon entering the reality phase, they may face the challenge of "both directing energy outward, leaving insufficient time to deepen the relationship's inner dimension." Conversely, a couple where both are high in introversion may be disadvantaged in the passion phase's "meeting opportunities," but will demonstrate strengths in "building deep intimacy" from the reality phase onward.

Karney & Bradbury (1995)'s Vulnerability-Stress-Adaptation Model shows that relationship success is determined by the interaction of "individual vulnerabilities (personality traits)," "external stress," and "adaptive processes (communication and problem-solving)." Personality traits are difficult to change, but adaptive processes can be learned.

Practical advice: (1) Recognize which stage your current relationship is in. (2) Be aware of the personality traits important at that stage and consider how to leverage your strengths. (3) For traits that represent weaknesses, compensate through deliberate skill-building. (4) Reframe stage transitions not as "problems" but as "growth opportunities." (5) Discuss stage changes openly with your partner and develop shared understanding.

Love is not about "finding the perfect partner" but about "walking through the stages together." Understanding that the traits required change at each stage, and supporting each other's growth, is the key to a fulfilling long-term relationship.