Lesbian, gay and bisexual (LGB) individuals are exposed to specific stressors due to their sexual minority status. One such stressor may result from the negative family reactions to one’s romantic partner. Encountering this stress may be especially harmful for LGB individuals’ emotional well-being, as it could be considered a “double rejection”: that of their partner and possibly their own sexual orientation. The stress surrounding family members’ negative attitudes about their partner may affect how one feels about their partner. Furthermore, there may be individual differences that affect how an individual may perceive and respond to this stress. Specifically, one’s attachment style could either exacerbate (anxious) or weaken (avoidant) the experiences of stress, which may influence the emotions they feel about their partner. Using 14-day daily diary data from 81 same-sex couples, the purpose of this study was to examine whether there was an association between daily perceptions of stress via negative family reactions to partner and negative partner-related emotions, and whether attachment insecurity (anxiety and avoidance) moderated this association. Individuals’ perceptions of stress via negative family reactions was found to be positively associated with their reports of negative emotions about one’s partner. Anxious and avoidant attachment did not moderate the association between perceptions of stress and negative emotions due to one’s partner. The finding suggests this specific stressor on negative emotions due to partner may be an intrapersonal process, in which case couple therapists can increase clients’ awareness of this stress and how it impacts their feelings towards their romantic partner.