Research suggests that forming a fresh framework of significance and reconstructing the spiritual underpinnings of one’s existence may empower a victim of sexual abuse to move beyond the grasp of the distressing incident. This longitudinal study investigates the interplay between forgiveness, spirituality that provides transcendent meaning-making, and mental well-being. The two-wave study involved 246 Polish women aged 18–45 who have experienced sexual assault. The procedure for both waves involved completing questionnaires assessing decisional and emotional forgiveness, spirituality, and well-being. Structural equation modeling shows the mediating effect of spirituality on the positive association between the state of forgiveness (as a latent variable including emotional and decisional dimensions) and mental well-being. The outcomes contribute to a deeper comprehension of the complex psychological processes triggered by sexual assault and extend the implications for tailored therapeutic interventions and support mechanisms for survivors. By highlighting the potential of spirituality as a conduit for enhancing mental well-being through forgiveness, this research offers valuable insights for developing comprehensive and effective healing strategies for individuals who have endured sexual assault.