Objective: The present study aimed to investigate the effectiveness of schema therapy (ST) on feelings of loneliness, cognitive emotion regulation, and distress tolerance among women injured by marital infidelity in Lahijan. Method: The current research was a quasi-experimental study. The population consisted of all women injured by marital infidelity living in Lahijan, Iran. Then, 500 participants were selected using the convenience sampling technique and were randomly assigned to an experimental and a control group. Participants in both groups were provided with several questionnaires to evaluate their feelings of loneliness, cognitive emotion regulation, and distress tolerance as the pretest procedure. Later, the experimental group was provided with 8 schema therapy sessions, while the control group did not receive any intervention. Then, the above questionnaires were distributed again among the participants in both groups, and the data were analyzed using the analysis of covariance method. Results: The results showed schema therapy significantly affected the investigated women’s loneliness, cognitive emotion regulation, and distress tolerance (p<0.01). Conclusion: Schema therapy, by working on EMS in patients who have a negative view of their abilities, feelings and emotions, is effective in correcting and changing their thoughts and beliefs. In the emotional dimension, the therapeutic schema challenges cognitive beliefs tied to emotional beliefs regarding experimental strategies. It causes a person to recognize the unsatisfied emotional needs that lead to the formation of EMS and emotional dysregulation and to seek a suitable solution.
