Perinatal loss represents a highly stressful life event that can significantly affect women’s emotional well-being and intimate relationships. Prior research suggests that adverse childhood experiences (ACEs), insecure romantic attachment (i.e., attachment anxiety and avoidance), feelings of guilt, and mental health problems may influence how couples cope with such losses. This cross-sectional study aimed to identify which combinations of these variables predict high or low levels of positive dyadic coping in women following perinatal loss. A convenience sample of 60 Spanish women who had experienced perinatal loss completed an online battery of self-report measures, including ACEs (ACE Questionnaire), romantic attachment (ECR-S), an ad hoc guilt item rating guilt intensity from 0 to 10, and a self-reported indicator of current mental health problems. Data were analyzed using fuzzy-set Qualitative Comparative Analysis (fsQCA), a set-theoretic statistical–analytic technique suited to identifying multiple causal pathways and configurations of conditions leading to a given outcome. Results showed that the absence of attachment avoidance was a necessary condition for high dyadic coping. Additionally, specific sufficient configurations emerged for both high and low coping. High dyadic coping was associated with combinations including low attachment avoidance, low attachment anxiety, and low guilt. Conversely, low dyadic coping was best explained by pathways involving high attachment avoidance together with high guilt or a history of childhood adversity. These configurations accounted for 74% of high-coping cases and 77% of low-coping cases. Overall, our findings highlight the importance of considering how psychological and relational factors interact to shape coping responses after perinatal loss. The configurational perspective offered by fsQCA underscores the need for flexible, personalized interventions that promote emotional closeness and strengthen emotion regulation within couples to foster adaptive coping following such a profound loss.