Purpose <p>The COVID-19 pandemic led many individuals to experience moral transgressions, exacerbating feelings of guilt and remorse. This study explored the role of the self-forgiveness of such transgressions in explaining their associations with psychological well-being and family conflict. We hypothesized that (a) higher levels of self-forgiveness would be associated with greater psychological well-being and reduced family conflict, (b) the perceived relevance of moral transgressions would be positively associated with self-forgiveness and indirectly associated with psychological well-being and family conflict through the mediation of self-forgiveness, and (c) the relationships between the variables of interest could vary across age.</p> Method <p>Adults (<i>N</i> = 277; M age = 30.04) completed anonymous online questionnaires assessing the relevance of transgressions committed, forgiveness and unforgiveness of self, psychological well-being, and family conflict during the first COVID-19 lockdown in Italy.</p> Results <p>Structural equation modeling revealed that transgression relevance was positively associated with both forgiveness and unforgiveness of self, and indirectly related to psychological well-being and family conflict via self-forgiveness. Greater forgiveness of self was related to greater eudaimonic well-being, whereas greater unforgiveness of self was linked to increased family conflict and reduced eudaimonic well-being. The findings also indicated that age moderated the relationship between forgiveness of self and hedonic well-being, with the association weakening as age increased.</p> Conclusions <p>The results highlight the importance of promoting self-forgiveness to enhance psychological resilience and familial stability, particularly during challenging times.</p>