Relationship Stress and Suicidal Ideation: A Daily Diary Study

Prior research on relationship stress and suicidal ideation has relied primarily on cross-sectional designs, limiting understanding of daily fluctuations and within-person processes. This study examined associations between relationship stress and suicidal ideation through the Interpersonal Theory of Suicide using a 10-day daily diary design. Participants (N = 84) were adults in romantic relationships reporting depressive symptoms and suicidal ideation. Multilevel modeling revealed that individuals with higher average relationship stress reported higher levels of perceived burdensomeness, thwarted belonging, and suicidal ideation. Within-person analyses showed that on days with elevated relationship stress, participants experienced same-day increases in burdensomeness, thwarted belonging, and suicidal ideation, but no next-day effects. Mediation analyses demonstrated that perceived burdensomeness mediated the same-day association between daily relationship stress and suicidal ideation. Findings suggest that relationship stress contributes to suicidal ideation by intensifying feelings of being a burden. Results support couple-focused interventions addressing relationship stress and perceived burdensomeness to reduce suicide risk.