Cheating in relationships is rarely about one simple cause. Research at the University of Maryland identified eight distinct motivations that drive people to be unfaithful, ranging from anger and sexual desire to neglect and low self-esteem. Understanding these psychological forces doesn’t excuse infidelity, but it does reveal patterns that help explain why it happens so frequently: roughly 20% of married men and 13% of married women report having cheated on a spouse.
The Eight Core Motivations
A University of Maryland research team surveyed 495 adults who admitted to cheating while in a committed relationship. After analyzing responses to nearly 80 questions, they identified eight factors that consistently drove infidelity:
- Anger: seeking revenge for a partner’s betrayal or perceived wrongdoing
- Sexual desire: feeling unsatisfied with sex in the relationship or wanting to try something new
- Lack of love: losing passion or falling out of love with a partner
- Neglect: not receiving enough love, respect, or attention
- Low commitment: one partner being less invested, or both partners not agreeing the relationship was exclusive
- Situation: circumstances outside a person’s normal life, such as being intoxicated, on vacation, or under extreme stress
- Esteem: using sexual attention from others to feel more desirable or independent
- Variety: wanting to experience as many sexual partners as possible
Most people who cheat don’t point to a single reason. These motivations overlap, and someone might feel neglected and simultaneously crave the self-esteem boost that comes from new attention. The key insight is that infidelity is often a response to something missing, whether that’s within the relationship or within the person.
How Attachment Style Plays a Role
The way you learned to bond with caregivers as a child shapes how you handle intimacy as an adult. Psychologists call these patterns “attachment styles,” and they turn out to be reliable predictors of infidelity. A meta-analysis published in the journal Heliyon found that both anxious and avoidant attachment styles were significantly associated with cheating in marriage.
People with avoidant attachment tend to pull away from emotional closeness. They value independence to the point of keeping partners at arm’s length, which can make outside relationships feel safer because they carry fewer emotional obligations. People with anxious attachment, on the other hand, crave constant reassurance. When they feel their partner isn’t meeting that need, they may seek validation elsewhere.
Interestingly, the meta-analysis found no link between what’s called “preoccupied” attachment (intense focus on one relationship) and infidelity. The strongest correlation was with fearful attachment, a style marked by wanting closeness but deeply fearing rejection. People with this pattern often sabotage their own relationships, and affairs can be one expression of that cycle.
The Brain Chemistry of New Attraction
Part of what makes affairs feel so compelling is pure neurochemistry. The brain’s reward system floods with feel-good chemicals during early-stage attraction, the same system involved in other pleasurable experiences. This creates a rush that long-term relationships, by their very nature, can’t sustain at the same intensity.
Research on the neurobiology of love shows that romantic attachment activates the brain’s reward circuitry while simultaneously quieting the regions responsible for critical social judgment and negative emotions. In practical terms, this means new attraction doesn’t just feel good. It also suppresses your ability to think critically about what you’re doing. The brain essentially lowers your defenses while amplifying the reward, which helps explain why otherwise thoughtful people make choices during affairs that seem irrational in hindsight.
Long-term partners still activate reward pathways, but the effect shifts over time from the intense dopamine-driven excitement of new love to a calmer, bonding-focused pattern. Some people interpret that shift as “losing the spark” and chase the neurological high of novelty rather than recognizing it as a normal transition.
Why Men and Women Often Cheat for Different Reasons
The motivational differences between men and women are consistent across multiple studies, though they’re tendencies, not rules. The University of Maryland research found that men were more likely to report being motivated by sexual desire, variety, and situational forces. Women were more likely to cite neglect.
A study published in the Journal of Social and Personal Relationships added more detail. Men were two to three times more likely than women to describe a primarily sexual motive for cheating. Women were significantly more likely to point to dissatisfaction with the relationship itself, rating that motive much higher than men did. The researchers noted that women engage in emotionally motivated infidelity at higher rates than men overall.
One important nuance: even when men reported a sexual motivation, it rarely existed in isolation. It was often intertwined with perceptions that their partner was emotionally negligent or inattentive. The stereotype that men cheat “just for sex” while women cheat “for feelings” is an oversimplification. Both genders are responding to a mix of emotional and physical needs, but they tend to emphasize different parts of that mix when explaining their behavior.
How People Justify It to Themselves
One of the most psychologically interesting aspects of cheating is how people manage the guilt. Most people who cheat still believe infidelity is wrong. That creates a painful tension between their actions and their values, a state psychologists call cognitive dissonance.
The most common strategy for resolving that tension is compartmentalization: mentally separating the affair from the rest of life so the two never have to coexist in the same thought. Someone might genuinely love their spouse while simultaneously maintaining a secret relationship, keeping the two in entirely different mental boxes. This isn’t a conscious strategy. It’s an unconscious defense mechanism that protects the person from the full weight of their contradiction.
Other people take different routes. Some convince themselves they did nothing wrong (“it was just texting, nothing physical happened”). Others revise their moral standards downward (“everyone does this, nobody’s perfect”). Still others rewrite the narrative of their primary relationship to cast themselves as the victim (“my partner drove me to this”). Each of these strategies serves the same purpose: shrinking the gap between “I’m a good person” and “I did something hurtful.” The mental energy required to maintain these justifications is one of the hidden psychological costs of infidelity, even for the person doing it.
Emotional Affairs vs. Physical Affairs
Not all infidelity involves sex. Emotional affairs happen when someone builds a close, often secret emotional bond with someone outside their relationship. There may be no physical contact at all, but the connection crosses boundaries through secrecy, emotional dependence, or confiding in someone else instead of a partner.
What makes emotional affairs particularly damaging is the sense of being emotionally replaced. Many betrayed partners report that discovering a deep emotional connection hurts more than learning about a one-time sexual encounter, because it suggests something was fundamentally missing from the relationship. Physical affairs, even when they “didn’t mean anything,” raise their own set of painful questions about respect, commitment, and safety. About 92% of women who admitted to infidelity described having an emotional affair, compared to 79% of men, which aligns with the broader pattern of women being more likely to form emotional connections outside relationships while men are more likely to engage in primarily physical ones.
How Social Media Has Blurred the Lines
Technology has introduced a gray area that previous generations didn’t have to navigate. The concept of “micro-cheating,” liking an ex’s photos, maintaining flirtatious text conversations, or keeping active dating profiles, reflects how digital interactions have made the boundaries of fidelity harder to define.
Research on social media and relationships has found that many people now believe evidence of infidelity can be found on a partner’s phone, which creates a cycle: ambiguous online behavior triggers suspicion, which leads to surveillance (reading texts, checking DMs), which partners then justify as “a right to the truth.” This dynamic can erode trust even when no actual cheating has occurred. The core psychological issue is that couples often haven’t explicitly agreed on what counts as crossing a line in digital spaces, leaving both partners operating under different assumptions about what’s acceptable.
What Happens to Relationships Afterward
Between 60% and 75% of couples stay together after infidelity is discovered, at least initially. But that number drops closer to 50% when researchers follow those couples over several years. Staying together and actually recovering are two very different outcomes.
The psychology of recovery depends heavily on which motivations drove the affair. Infidelity rooted in situational factors or variety, where the person is otherwise satisfied with their relationship, tends to be easier to work through than cheating driven by lack of love or deep neglect, which signals structural problems in the partnership. The betrayed partner’s attachment style also matters. Those with anxious attachment may struggle more intensely with trust but may also be more motivated to repair the relationship, while avoidant partners are more likely to shut down emotionally and withdraw.
What research consistently shows is that the affair itself is rarely the core problem. It’s typically a symptom of underlying dynamics, whether those are personal (attachment wounds, self-esteem issues, poor impulse control) or relational (communication breakdowns, emotional distance, unmet needs). Couples who treat infidelity as information about what went wrong, rather than solely as a moral failing, tend to have better outcomes regardless of whether they stay together or separate.