In this electronic diary study (N = 127 couples), we examined how a diabetic partner’s symptoms and distress are associated with relationship interactions over 24 days. Using dyadic multilevel models, we examined the effects of patients’ daily diabetes symptom severity and diabetes-specific distress on each partner’s evaluations of their daily interaction enjoyment and tension. For both patients and spouses, diabetes symptoms were associated with a decrease in enjoyment and an increase in tension. For spouses, but not for patients, daily diabetes distress was marginally associated with an increase in tension. Among spouses whose patients’ diabetes was of longer duration, the negative association of symptoms and spouses’ enjoyment was stronger. These findings suggest that the stress of patients’ disease and distress affects both partners on a daily basis.