en خانواده و گروه درماني Family and group therapy پژوهشي Original Research Article <div style="text-align: justify;"><span style="font-size:14px;"><span style="font-family:Tahoma;"><span style="line-height:2;"><strong>Objective</strong>: Marital infidelity often leads to significant psychological distress, including diminished self-esteem, depression, and anxiety, profoundly affecting women&rsquo;s mental well-being. This study aimed to evaluate the effectiveness of compassion-focused therapy (CFT) in enhancing forgiveness and reducing self-criticism and repetitive negative thoughts among women impacted by marital infidelity in Ahvaz City, Iran.<br> <strong>Methods</strong>: A quasi-experimental study with a pre-test and post-test design, including a control group, was conducted. Thirty married women affected by marital infidelity, recruited via convenience sampling from counseling centers in Ahvaz City (January&ndash;March 2025), were randomly assigned to an experimental group (n=15) or a control group (n=15). The experimental group received eight 90-minute CFT sessions twice a week, while the control group received no intervention. Data were collected using the forgiveness scale (FS), self-criticism levels scale, and repetitive thoughts questionnaire (RTQ) and analyzed using analysis of covariance (ANCOVA) in SPSS software, version 27.&nbsp;<br> <strong>Results</strong>: CFT led to a significant increase in forgiveness and a notable reduction in self-criticism and repetitive negative thoughts in the experimental group compared to the control group (P<0.001). The observed effects were substantial, with large effect sizes across all measures (forgiveness: &eta;p2=0.71, Cohen&rsquo;s d=1.92; self-criticism: &eta;p2=0.78, Cohen&rsquo;s d=2.34; repetitive negative thoughts: &eta;p2=0.69, Cohen&rsquo;s d=1.85).<br> <strong>Conclusion</strong>: CFT is an effective intervention for improving the psychological well-being of women affected by marital infidelity, promoting forgiveness and reducing negative cognitive patterns.</span></span></span></div> Compassion-focused therapy (CFT), Forgiveness, Self-criticism, Negative thoughts, Marital infidelity 347 354 http://jpcp.uswr.ac.ir/browse.php?a_code=A-10-1069-1&slc_lang=en&sid=1 Zahra Ghafari ghafarizra@gmail.com 0000-0002-7252-7595 No Department of Counseling, Ahv.C., Islamic Azad University, Ahvaz, Iran. Mehdi Hoseinzadeh hoseinzadehmd@gmail.com 0000-0002-8626-9857 Yes Department of Counseling, Ahv.C., Islamic Azad University, Ahvaz, Iran. Mehdi Hashemipour hashemipourmd@gmail.com 0009-0000-3003-9377 No Department of Psychology, And.C., Islamic Azad University, Andimeshk, Iran.