The Relationship Intimacy Model of Couple Adaptation to Cancer (RIM; Manne & Badr, 2008) theorizes that relationship-enhancing behaviors increase couples’ intimacy and, in turn, improves psychological and relationship adaptation to cancer. In contrast, relationship-compromising behaviors reduce intimacy, which in turn negatively impacts outcomes. This model has been applied to examine the relationship experiences of couples along the cancer survivorship spectrum. Yet, it is unknown if the model accounts for relationship dynamics in situations outside the cancer context. The primary goal of this study is to test the validity of the RIM framework within general relationship dynamics and during a health event. Participants were asked to draw upon their interactions with their romantic partners, relationship intimacy, relationship satisfaction, and psychological adaptation in general daily life as well as during a recent health event. Participants (N = 505) were on average 20.1 (SD = 1.94) years old, female (75%), Hispanic/Latino (66.3%), and in committed relationships. Stepwise linear regression analyses revealed that in the context of general daily life: (1) partner responsiveness was positively associated with intimacy, positive affect, and relationship satisfaction, and negatively associated with negative affect; (2) perceived self-disclosure was positively associated with intimacy, positive affect, and relationship satisfaction; (3) both emotional suppression and self-demand/partner-withdraw were positively associated with intimacy, negative affect, and depression, and negatively associated with relationship satisfaction; and (4) partner-demand/self-withdraw was positively associated with intimacy and positive affect. In the context of a health event: (1) partner responsiveness was positively associated with intimacy, positive affect, and relationship satisfaction; (2) emotional suppression was negatively associated with positive affect and couples relationship satisfaction, and positively associated with negative affect and intrusiveness and avoidance; (3) criticism was negatively associated with relationship satisfaction; (4) partner-demand/self-withdraw was positively associated with negative affect and intrusiveness and avoidance; (5) self-demand/partner-withdraw was positively associated with intimacy. Mediational analyses revealed that in general daily life, intimacy mediated the relationships between: (1) partner responsiveness, emotional suppression, self-demand/partner-withdraw, partner-demand/self-withdraw and positive affect (2) partner responsiveness, partner-demand/self-withdraw and negative affect; and (3) relationship satisfaction and partner responsiveness, emotional suppression, self-demand/partner-withdraw, partner-demand/self-withdraw. During a health event, intimacy mediated the relationships between: (1) positive affect and partner’s responsiveness, self-demand/partner-withdraw, and (2) negative affect and partner responsiveness. This study highlights important components of relationship behaviors that may predict relationship satisfaction and adaptation to health events and in general relationship dynamics. These findings can improve efforts to tailor couples-based interventions to promote adaptive coping and adjustment to different illness experiences and for relationship satisfaction in everyday life.