There are few moral issues that enjoy as wide consensus as infidelity: An overwhelming majority of adults, in North America and Europe, believe that infidelity is wrong (Blow and Hartnett, 2005). But despite this widespread social censure, infidelity is fairly common. Estimates suggest that as many as 10-25% of married couples in the U.S. experience sexual infidelity at least once (Atkins et al., 2001; Blow and Hartnett, 2005; Elmslie and Tebaldi, 2008).
Why is it that so many spouses cheat?
Motivations for Infidelity
Not unsurprisingly, motivations for cheating vary, as does the nature of the illicit union—one-night stands or long-term affairs, purely sexual liaisons or strong emotional connections (Blow and Hartnett, 2005). The majority of cheating spouses, regardless of gender, report that their extramarital affairs satisfied emotional and sexual needs equally (Thompson, 1984), although men are more likely than women to report a primarily sexual motivation while women are more likely to be motivated by dissatisfaction with the primary relationship (Barta and Kiene, 2005; Thompson, 1984). However, men and women are equally likely to cite emotional or sexual motivations if their primary relationship is lacking in either regard (Omarzu et al., 2012).
For both genders, greater dissatisfaction with the primary union promotes emotionally closer relationships with cheating partners (Allen and Rhoades, 2008).
Similarity and Satisfaction
Couples tend to match each other on many characteristics, including education, income, physical attractiveness, religious views, interests, and attitudes. Those couples who do not match on one or more important trait may be more vulnerable to infidelity, perhaps because they experience higher levels of marital dissatisfaction. For example, couples with the same religion and educational level are less likely to experience infidelity, and couples in which both partners have a college degree enjoy especially low rates of infidelity (Brooks and Monaco, 2013).
Interestingly, women with higher levels of education than their spouses may be more likely to cheat than comparable women with equally-educated spouses (Forste and Tanfer, 1996). This is consistent with the argument that spouses with greater socioeconomic resources will be less afraid of jeopardizing their primary relationship through infidelity (Forste and Tanfer, 1996). Similarly, individuals may be more likely to cheat when they are employed but their spouse is not: This effect appears to be stronger for sole-breadwinner women than for sole-breadwinner men (Brooks and Monaco, 2013; Atkins et al., 2001). Shared employment status might reflect spousal similarity, and the shared experience of employment might strengthen couple bonds. Conversely, a sole provider may have greater autonomy to pursue alternative partners and may anticipate lower costs if their partner discovers their infidelity.
Given the popular stereotype that female infidelity is far rarer than male infidelity, the findings that motivations for cheating are similar for women and men may be surprising. It might be equally surprising that women’s socioeconomic autonomy predicts their infidelity—that is, women are especially likely to cheat when they have more education than their husband and when they are employed and their husband is not . But there may be less of a gender gap in cheating than is commonly supposed.
Historically, men have generally reported higher rates of infidelity, but the gender gap appears to be diminishing as women gain socioeconomic and sexual autonomy. For example, using data from the General Social Survey, multiple independent studies find a large gender gap in reported infidelity among older cohorts but a small or non-existent gap among middle-aged and younger adults (Atkins et al., 2001; Elmslie and Tebaldi, 2008). This absence of a gender difference in reported infidelity is reflected in other recent studies of college students (Brand et al., 2007; Lambert et al., 2014).
Moreover, even when a gender gap in reported infidelity is evident, it might result (at least in part) from gendered reporting bias. Fisher and Brunell (2014) find that the gender gap in reported romantic cheating disappears when undergraduates believe they are being monitored by a lie detector. The authors suggest that much of the apparent gender gap in infidelity in survey data may reflect a gender difference in reporting rather than a gender difference in actual behavior.
In other words, men may exaggerate infidelity while women understate it.
Infidelity and Fidelity
Most obviously, discovering infidelity is often very painful to the deceived spouse (Blow and Hartnett, 2005) and infidelity is very damaging to the primary relationship, often resulting in divorce (DeMaris, 2013). But these costs may not be effective deterrents. For both genders, dissatisfaction with the current relationship is often a central motivation for infidelity—and so hurting the spouse or damaging the marriage just may not matter to dissatisfied spouses. Given these weak disincentives for infidelity, cheating is likely to continue, despite social disapproval. Websites such as AshleyMadison.com, designed to facilitate extramarital affairs, further lower the costs of cheating. Perhaps we should be less surprised that infidelity is common despite social disapprobation, and instead be grateful that most of our partners don't cheat.
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