In the Shadow of Another’s Bliss

: Understanding the Effects of Image-based Cross-Relationship Comparisons on the Relationship Attitudes of Young Adults

Abstract

Despite widespread interest in how social media shapes relationships, little is known about the processes through which it influences relationship attitudes. This thesis examined cross-relationship comparisons (CRCs) in response to idealised relationship images in a multi-study, multi-relationship framework spanning romantic relationships and friendships. While CRCs have been discussed as an important way in which people respond to idealised online content (Morry et al., 2018; Thai et al., 2022), prior research has not established whether such comparisons reliably occur, what forms they take, or how they affect one’s relationship attitudes. Consequently, this thesis sought to investigate whether idealised relationship images spontaneously elicit CRCs, what forms these comparisons take, and whether they influence attitudes toward one’s own or others’ relationships. With these goals in mind, six preregistered studies were conducted. A stimulus-development study established a database of idealised and non-idealised relationship photographs for subsequent research (Study 1). The spontaneous prevalence, directionality, and emotional outcomes of CRCs were examined using a thought-listing paradigm (Study 2). Two pre- to post-exposure experiments (one on romantic relationships and one on friendships) tested whether viewing idealised relationship images altered relationship attitudes (Studies 3 and 4). Two further experiments (one on romantic relationships and one on friendships) manipulated CRC directionality by combining a relationship dissatisfaction prime with exposure to idealised versus non-idealised images to test effects on relationship attitudes (Studies 5 and 6). Across studies, five consistent patterns emerged. First, idealised relationship images were capable of triggering CRCs, although this varied. Second, CRC directionality showed considerable diversity. Third, CRCs were accompanied by a range of emotional responses, potentially suggesting greater complexity than previously assumed. Fourth, viewing idealised relationship images negatively affected own-relationship attitudes. Fifth, emotional responses moderated these effects, with negative emotions such as envy amplifying them and positive emotions such as optimism attenuating them.

Date of Award	17 Mar 2026
Original language	English
Awarding Institution	University of Bristol
Supervisor	Susanne Quadflieg (Supervisor) & Angela C M Rowe (Supervisor)