KMAN Publication Inc. (KMANPUB) Applied Family Therapy Journal (AFTJ) 3041-8798 In Press 2027 01 01 The Mediating Role of Guilt in the Relationship Between Dark Personality Traits and Tendency Toward Marital Infidelity Among Married Individuals The Mediating Role of Guilt in the Relationship Between Dark Personality Traits and Tendency Toward Marital Infidelity Among Married Individuals 1 13 EN Journal Article 2026 04 05 <p><strong>Objective:</strong> This study aimed to examine the mediating role of guilt in the relationship between dark personality traits and the tendency toward marital infidelity among married individuals.</p> <p><strong>Methods and Materials: </strong>This quantitative study used a descriptive-correlational design based on path analysis. The statistical population included married individuals residing in Neyshabur, Iran, in 2024. A sample of 300 participants was selected through convenience sampling. Data were collected using the Dirty Dozen Dark Personality Traits Scale developed by Jonason and Webster, the Guilt Inventory developed by Kugler and Jones, and the Marital Infidelity Tendency Questionnaire developed by Whatley. The collected data were analyzed using SPSS version 27 and AMOS version 24. Pearson correlation coefficients and path analysis were applied to test the hypothesized direct and indirect relationships among narcissism, Machiavellianism, antisocial traits, guilt, and tendency toward marital infidelity.</p> <p><strong>Findings: </strong>The revised structural model showed acceptable fit to the data, with χ² = 1.41, df = 1, RMSEA = .038, GFI = .99, AGFI = .98, NFI = .97, IFI = 1.00, and CFI = 1.00. Machiavellianism had a significant negative effect on guilt (β = −.24, p = .001), and antisocial traits also had a significant negative effect on guilt (β = −.56, p = .044). Guilt had a significant negative effect on tendency toward marital infidelity (β = −.10, p = .005). Machiavellianism (β = .41, p = .029) and antisocial traits (β = .47, p = .006) had significant positive direct effects on tendency toward marital infidelity. The indirect effects of Machiavellianism (β = .04, p = .006) and antisocial traits (β = .02, p = .033) on infidelity tendency through guilt were significant, whereas the indirect effect of narcissism was not significant (p = .743).</p> <p><strong>Conclusion: </strong>The findings indicate that guilt partially mediates the relationship between dark personality traits and tendency toward marital infidelity. Higher Machiavellian and antisocial traits were associated with lower guilt and greater infidelity tendency. Therefore, assessing dark personality traits and strengthening guilt-related moral responsibility may be useful in marital counseling and preventive interventions.</p> https://journals.kmanpub.com/index.php/aftj/article/download/5717/10833