UC San Diego

From a functional perspective, jealousy may help protect an important relationship against a rival regardless of the types of relationships. This dissertation focuses on a valuable nonromantic relationship—namely, same-sex friendship— and investigates how people try to maintain it in a jealousy situation by examining a wide range of responses, from prosocial to antisocial. While answering this question, I also aim to overcome a major obstacle in the jealousy literature by assessing jealousy via methods reflecting more real-life situations, such as experimental manipulation in the lab and a diary method. Chapter 1, which elicited jealousy via a recall and hypothetical scenarios, finds that adults often experience friendship jealousy and when they do, they engage in both prosocial and antisocial behaviors. Chapter 2 uses an in-lab manipulation in actual same-sex friends in an ethical manner, and successfully changed self-reported emotions and behaviors. Participants in the jealousy condition were less likely to take risks in their friendships by engaging in less confrontation and acting more nicely towards rivals, most of whom were also friends with participants. Finally, using a 14-day diary method, Chapter 3 examines the early and late processes of friendship jealousy in more naturally occurring situations, and the effects of existing friendship quality as a moderator on each process. Consistent with the previous findings, real-life friendship jealousy increased both prosocial and antisocial behaviors in individuals. Moreover, the study found that better friendship quality provided a buffer against perceiving the presence of rival however, once the rival became threatening, it intensified the motivation to protect their friendships. Together, this dissertation extends the jealousy literature and our understanding of how people react to friendship jealousy and offers new insights on how jealousy unfolds in real life situations.