A Psychologist Explains The Evolutionary Mechanisms Behind Breakups

The emotional turmoil of a breakup has deep roots in our evolution. Here's where they came from, and how they manifest.

By Mark Travers, Ph.D. | April 21, 2025

When you spend years building a life around another person, only to have it suddenly vanish, it can feel like nature itself has dealt you a cruel hand. Breakups can stir up a cocktail of reactions in this sense: we may become listless, irrational or even enraged.

While very personal, each of these reactions can be traced back to our evolution: our primal need for reproduction, protection and survival. From the overwhelming sadness that grips you to the urge to reinvent yourself, January 2025 research from Evolutionary Psychology provides us with a new lens to understand these responses.

According to the study, there are three broad categories of reactions an individual can have to a breakup — each comprised of different manifestations. The average person can experience anywhere between four and nine of these reaction subtypes all at once. Here's a breakdown of each, and how we can make sense of them through evolution.

1. Sadness And Depression

Most people find themselves overwhelmed by waves of sadness in the wake of a breakup. They might spend evenings replaying their last moments together with their ex-partner, desperately trying to figure out where it all went wrong. Some might even resort to stalking their exes' social media for clues. This might sound all too familiar; fortunately, the research reassures us it's entirely natural, too.

According to the study, 92% of individuals experience intense feelings of sadness or depression after a breakup. From an evolutionary standpoint, this emotional collapse reflects the steep costs associated with losing a partner.

For our ancestors, forming a committed relationship wasn't a matter of romance; it was their only way to ensure survival. A partner meant shared resources, protection and greater reproductive potential. While we may not face the same threats as our ancestors did, our DNA is nevertheless encoded to see breakups as a potential setback in "fitness" or survival. And, as the study suggests, this can manifest in a few ways:

• Trying to change their mind. Many people find themselves clinging to the hope of reconciliation. This attempt to change the partner's mind might be driven by the subconscious awareness that losing an intimate partner means losing out on mutual benefits — like security and resource sharing. In other words, if the partner were to stay, the individual would continue to enjoy evolutionary fitness-enhancing advantages.
• Seeking an explanation. This is the second most common post-breakup reaction. The study noted that 85% of breakup survivors search for explanations, all in an attempt to make sense of the cause of the split. This behavior can be understood as a mental strategy to re-learn and adjust for future relationships — an adaptive mechanism that urges us to analyze what might have led to a decrease in reproductive or survival prospects.
• Spying on the ex. Even in the wake of separation, many people try to gain insights into their ex-partner's life. Spying is one of our greatest means to gauge whether the other person might have found a 'better match' — a mate of higher fitness value. It's a way of evaluating our own standing in the dynamics of mate selection that affect survival.
• Seeking professional help. Although it might seem like a modern intervention, the inclination to talk to a therapist or a trusted friend is tied to our deeply human need for social support in times of loss. Evolutionarily, seeking help allowed individuals to form alliances and find solace in community support; this, in turn, helped in managing the stress of partner loss.

Despite the scientific neatness of these evolutionary explanations, the experience of sadness in a breakup is anything but orderly. There are days when you might wake up feeling numb, and others when the weight of memories seems unbearable. The twists and turns of these emotions can make you question, cry, laugh and remember all at once. Your heart is not a calculator; it's completely normal for your grief to feel chaotic and overwhelming.

2. Accepting And Forgetting

Almost everyone is bound to initially struggle with a breakup. However, after a few weeks, some individuals may begin to notice a subtle shift in how they feel — a lot more quickly than they'd anticipate. Instead of fixating on lost love, they may opt instead to start cutting off contact, dedicate more time to their hobbies and reconnect with old friends.

For these individuals, the mind — either slowly or immediately — transitions from ruminating the past to engaging in activities that help rebuild their life. This reaction, to accept and forget, comprises behaviors that allow an individual to regain control and reclaim their day-to-day functioning. This category includes:

• Going no-contact. The deliberate choice to disengage from an ex is a common strategy. Reducing reminders of the past is one of the most effective ways to allocate focus on self-recovery. Evolutionarily, this intentional detachment can be seen as an adaptive move to protect oneself from further emotional costs — which frees up psychological resources for new social opportunities.
• Acceptance. Coming to terms with the breakup is a hard-won realization that not every relationship will benefit us in the long run, despite how much your brain and heart initially protests. Accepting the end of a relationship is a way to minimize further fitness losses and prepare oneself for the future — or, for a potentially more rewarding partnership.
• Occupying and distracting the mind. With roughly 81% of individuals turning to distractions — making it the third most common reaction — there is an implicit evolutionary logic at work. When a relationship ends, diverting one's attention through engaging activities (like hobbies, fitness or work) allows the mind to recalibrate. This not only reduces the immediate emotional pain, but also rebuilds your internal resource pool that no longer needs to be devoted to maintaining the relationship.

On paper, the evolutionary logic behind "accepting and forgetting" suggests a tidy process of discarding the old to embrace the new. But in practice, moving on is rarely a cut and dry process. Some days, you might feel like you're making monumental strides toward healing; on others, memories come crashing in unparalleled force. It's perfectly human to struggle with letting go. Loss and longing can be persistent, messy and non-linear — so, don't be hard on yourself if you're not as quick to move on as your ancestors or peers might have been.

3. Aggression

For some individuals, the turmoil following a breakup can give rise to an inexplicable burst of anger. They might become rude, vengeful, confrontational or — in extreme cases — perhaps even physical. Although less common, physical and psychological aggression is a well-documented response in the wake of relationship dissolution. The 2025 study lends support to this, and further details several behaviors in this category:

• Revenge sex. Engaging in sexual activity with the intent of asserting oneself, or as a reaction to the perceived betrayal, also reflects our innermost primal drives. Evolutionary theory suggests that reproduction and mating opportunities are inextricably linked; in this sense, some individuals might do whatever it takes to reestablish their reproductive value — even if it comes with risky emotional or physical complications.
• Unadulterated anger. Anger is a powerful emotion that signals a threat. From an evolutionary standpoint, anger prepares the body for a fight-or-flight response, as it mobilizes physical resources to counter an "adversary." From the standpoint of a breakup, however, this anger is just one of many natural responses to perceived injustice of losing a partner who contributed significantly to one's survival odds.
• Physical aggression. Thankfully, only about 4% of those studied were found to resort to physical acts, making it the second rarest response-type. Such reactions cannot and should not be condoned or validated in any way, given the immense emotional and physical harm they can cause. Yet, physical outbursts can still be understood as an extreme stress response: they're a vestige of the need to assert dominance or retaliate against a perceived threat to one's fitness. While uncommon and undesirable, such behaviors may have historically functioned as a way to ward off competitors or reclaim lost status.
• Threatening suicide. The rarest subcategory (at about 2%) is the most extreme expression of distress: the threat of suicide. While it might appear counterproductive from an evolutionary perspective, it's important to understand that these acts are often a final resort from someone whose internal balance has been overdriven by loss. In evolutionary history, such behaviors might have been co-opted from more general stress responses. Though, in modern society, they generally serve as either a desperate cry for help, or as one of the most insidious forms of manipulation. Although nonphysical, the latter can have just as harmful an emotional effect on the recipient as a physical or violent outburst — making it just as unconscionable.

Science may neatly categorize these aggressive reactions, but the real anger you feel in the aftermath of a breakup is anything but orderly. That doesn't mean acting on those feelings in harmful ways is okay, but it does mean that struggling with big, uncomfortable emotions is only human. You might feel betrayed, rejected or furious; those feelings deserve professional attention and care — even more so if they could put you or your ex in danger. Evolutionary theory can help explain why we feel so shaken, but it will never fully capture the storm of thoughts, impulses and heartache that often follows a breakup.

Still reeling from your breakup? Take this science-backed test to learn if you're ready to start your healing journey: Breakup Distress Scale

A similar version of this article can also be found on Forbes.com, here.