Anxious and avoidant attachment may be detrimental for diabetes distress and management. Additionally, individuals’ perceptions of their partner’s involvement may affect these associations. The study explored cross-sectionally and at the daily level whether anxious and avoidant attachment associated with diabetes distress or stressors and diabetes management, and whether higher perceived collaboration and support (C&S) moderated associations between attachment and diabetes management. Individuals with type 1 diabetes (N = 199; M age = 46.82; 52.3% women) completed measures of diabetes distress, diabetes-related C&S, self-care, average blood glucose (hemoglobin A1c), and attachment insecurity, and daily diary measures of diabetes-related C&S, diabetes stressors, mean blood glucose, and self-care. Higher anxious and avoidant attachment associated with higher diabetes distress. Higher anxious attachment associated with more daily stressors. Anxious attachment associated with lower self-care. C&S did not moderate any associations. Findings highlight the need to consider attachment when designing interventions to reduce diabetes-related distress.