["Family Process, Volume 65, Issue 3, September 2026. ", "\nABSTRACT\nChronic cardiac illness often places substantial psychological and relational strain on patients and their intimate partners. Demoralization, a state of hopelessness, low coping efficacy, and perceived incompetence, can emerge in both partners, particularly when illness‐related communication is ineffective. Understanding how couples communicate about the illness is therefore critical for supporting each partner's mental health. This study examined how illness‐related communication is associated with demoralization in couples in which the male partner has a cardiac disease. Specifically, we investigated how each partner's communication relates to their own and their partner's experiences of demoralization (actor and partner effects). A cross‐sectional study was conducted with 117 heterosexual couples (N = 234 individuals) in which the male partner was enrolled in a cardiac rehabilitation program in Israel. Dyadic analysis using the actor‐partner interdependence model (APIM) was employed. Results indicated that 19% of male patients and 17% of female partners met criteria for demoralization. Dyadic analysis revealed significant actor and partner effects, indicating that both an individual's own and their partner's effective communication were associated with lower demoralization. Sex moderated these effects: female partners benefited primarily from their own communication, whereas male patients benefited from their partner's communication. These findings suggest that integrating structured dyadic communication training into cardiac rehabilitation programs may reduce demoralization and improve psychological adjustment among couples coping with chronic illness.\n"]