Why Sexual Narcissists Make Unfaithful Partners

New research into why some partners are prone to stray.

Posted Dec 27, 2014

The excessive self-focus and entitlement we associate with narcissism would seem to predispose people high on this trait to think only of meeting their own needs in a relationship. The minute they find a new and enticing partner, one might assume, they’ll be off and running to explore and perhaps exploit this target of desire.

If you’ve been in a relationship with a narcissist, you’re probably already aware of the characteristic behaviors associated with this personality type: The partner hogs the mirror, constantly asks for favors, and seems to care little about what you think. When it comes to sexuality, the narcissistic individual expects you to do the satisfying, while you patiently wait to have your needs met.

It’s also possible that a narcissistic partner is more likely to stray, and as a result, you’re constantly on guard for evidence of cheating. You wonder if the partner will act on the impulse to hook up with the attractive new assistant at work, a parent at daycare, or the new neighbor down the street. Because people high in narcissism want to look good and be the center of attention, it would make sense that they want to associate with others who enhance their social standing—highly attractive people would seem to fit the bill.

As we have recently discovered, though, even if your partner seems to meet at least some of the general criteria for narcissism, you may not have to worry.

In a newly-published study, Florida State University psychologist James McNulty and Laura Widman of Duke’s School of Medicine investigated the relationship between sexual narcissism and infidelity in the early stages of marriage.

Using a sample of 123 newlyweds, McNulty and Widman requested that participants complete a set of questionnaires to measure narcissism and its relationship to infidelity, marital satisfaction, and sexual satisfaction. One group of couples, followed over 4 years, completed measures of general narcissism only; the second group, tracked over a 1-year period, also completed a test measuring sexual narcissism.  

The strength of this study, compared to many others on similar topics, is that both partners in a couple completed the questionnaires; that the partners were actually older and in a more committed relationship than we see in typical studies of college students; and that the partners were followed up over time.

People scoring high on the sexual narcissism scale are more likely to agree with a statement such as “I really know how to please my spouse sexually.” Other facets of sexual narcissism, in addition to expressing grandiose thoughts about your sexual proficiency, include sexual entitlement (feeling that you deserve to have the kind of sex you want), lacking sexual empathy (failing to know what your partner wants), and being sexually exploitative (using people to satisfy your needs).

Over the course of the study, McNulty and Widman reported that 5% of their newlyweds engaged in infidelity; about half of those individuals were the wives. As they expected, the research team found that those high in sexual narcissism were indeed more likely to be involved in an extramarital affair. These findings held even when controlling for general narcissism, satisfaction with the marriage and with sex in the marriage, and partner’s scores on each of these measures.

Each facet of sexual narcissism seemed to play a role in relating to infidelity. However, slightly stronger relationships emerged for sexual entitlement and sexual grandiosity. There were some gender differences—husbands who lacked sexual empathy were more likely to be unfaithful, for example. It is somewhat ironic that partners who believed that they were sexually more proficient but who also expressed lack of empathy (especially husbands) were the ones who reported that they cheated.

These findings suggest that being a sexual narcissist increases the likelihood that people will cheat on their partners. There were also indications that having a sexually narcissistic partner created its own set of problems. Overall, having a narcissistic partner didn’t seem to increase the chances of your being unfaithful. However, there were predictive relationships between a partner’s sexual narcissism and infidelity among several of the narcissism facets. People with spouses who believed they were entitled to sex were more likely to cheat, as were people whose spouses had an inflated sense of their own sexual skills.

As you might expect, people who felt sexually satisfied in a relationship were less likely to cheat. However, overall marital satisfaction didn’t predict infidelity once the researchers controlled for the effects of sexual narcissism and sexual satisfaction. In other words, overall feelings toward the relationship didn’t predict the likelihood of cheating. Instead, it was high levels of sexual narcissism—not narcissism in general—that seemed to set the stage for people to seek sex outside the marriage.

This study was unique in using sexual narcissism, not narcissism in general, to predict levels of infidelity. Previous studies using overall narcissism measures hadn’t established a consistent pattern of relationships to unfaithfulness. The findings suggest that if you want to predict who will cheat in a marriage, it’s important to look at the specific domain of sexual narcissism and not general narcissistic tendencies.

From the standpoint of people’s sense of well-being, infidelity tends to have negative consequences. You may or may not believe that monogamy is essential for a relationship’s health, but for open marriages or other polyamorous relationships to work, all participants need to be on board. When a partner is unfaithful to you, it can hurt your mental health as well as the health of your relationship. Not all unfaithful partners are sexual narcissists, but for people high on the facets of this trait, the risk is greater that they, or their partners, will cheat.

To sum up: Taking account of your (and your partner’s) levels of sexual narcissism seems to be an important step toward ensuring that your relationship will stay on course. Using the facets of sexual narcissism as a guide, ask yourself honestly whether or not you tend to exploit your partner sexually; think you’re more adept sexually than you might be; lack the ability to sense what your partner wants; and feel that you’re entitled to sex with your partner. Take this one step further and ask whether you sense these tendencies in your partner. If so, this study’s findings suggest that your relationship will be more likely to endure if you are able to address, and possibly fix, problems before they begin.

Personality isn’t necessarily that amenable to change, but change is possible. Addressing the problem of sexual narcissism can help you maintain your sexual fulfillment now and into the future.

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Copyright Susan Krauss Whitbourne 2014


McNulty, J. K., & Widman, L. (2014). Sexual narcissism and infidelity in early marriage. Archives Of Sexual Behavior43(7), 1315-1325. doi:10.1007/s10508-014-0282-6