||Collaboration and support (C&S) from romantic partners is often, but not always, linked with better diabetes management. Attachment may explain when C&S is beneficial. More insecurely attached individuals may benefit more (e.g., higher anxious attachment) or less (e.g., higher avoidant attachment) from higher C&S and these differences may be amplified under higher distress both between and within persons. The objective of the study was to understand how attachment moderates associations between C&S, diabetes distress, and diabetes management (i.e., adherence, glycemic control, daily mean blood glucose). Individuals (N = 199, Mage = 46.35; 52.3% women) with type 1 diabetes in romantic partnerships completed cross-sectional surveys and a 14-day daily diary that assessed adherence, C&S, and distress to examine between- (surveys) and within-person (diary) associations. HbA1c was gathered from in-lab assays and blood glucose gathered from glucometers. Results indicate that higher anxious attachment associated with lower C&S and lower adherence between persons. C&S did not independently associate with diabetes management. Anxious attachment interacted with diabetes distress, such that higher distress was detrimental for glycemic control only for those with lower anxious attachment. Within persons, daily C&S was only beneficial for adherence when accounting for individuals' diabetes-related distress, and stressors and attachment insecurity did not moderate these associations. Results suggest that while attachment insecurity has meaningful implications for diabetes management, it does not moderate C&S and C&S itself does not significantly bolster diabetes management. These findings highlight the need to further examine how attachment insecurity operates to affect diabetes care.