Are You Two Just Friends? Emotional and Sexual Infidelity Across Sexual Orientations

  • Samantha Yim Department of Psychology, The University of California, San Diego, USA
  • Nicole Tanzer Department of Psychology, The University of California, San Diego, USA
  • Margaret Satchwell Department of Psychology, The University of California, San Diego, USA
  • Coty Chen Department of Psychology, The University of California, San Diego, USA
  • Juanshu Wu Department of Psychology, The University of California, San Diego, USA
  • Daniel Javidi Department of Psychology, The University of California, San Diego, USA
  • Marissa Hensley Department of Psychology, The University of California, San Diego, USA
  • Catherine Phan Department of Psychology, The University of California, San Diego, USA
  • Jarryd Willis Department of Psychology, The University of California, San Diego, USA
Keywords: infidelity, relationships, sexuality, friendship


Lesbians are unlikely to ask if it is possible for women and women to be friends. Bisexuals have friends of each sex. It seems that it is primarily heterosexuals who have trouble with sex-of-attraction friendships. This study examined how participants perceived the emotional and sexual infidelity of their partner’s relationship with a friend differing across sexuality and biological sex. Our participants consisted of a combined sample across two studies (n = 532), participants completed measures of their perceived emotional and sexual infidelity towards 10 controlled behaviors that their partners committed with the partner’s friends. The data revealed that participants were more concerned with perceived emotional infidelity with sex(es)-of-attraction friends as a function of participants’ sexual orientation, sex, and their lover’s sexual orientation. Our evidence shows that when in relationships, people feel most threatened by the friend of the partner who possesses the same biological machinery as them. Furthermore, results suggest that people are also more likely to be threatened by their partner’s friend, who may have a mutual attraction towards their partner. The effect of the same biological machinery and the mutual attraction on perceived infidelity is additive. The pattern is seen across heterosexual, homosexual, and bisexual relationships.


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Emotional & Sexuality Infidelity Concern Scores for Straight Women with Straight Men