Intensive Multi-Couple Therapy for PTSD Versus Relationship Education in Military Couples

The goal of this clinical trial is to test an abbreviated, intensive, multi-couple group version of cognitive-behavioral conjoint therapy for PTSD (AIM-CBCT for PTSD) in an active military and veteran population. The main questions it aims to answer are: * Does AIM-CBCT for PTSD improve PTSD symptoms? * Does AIM-CBCT for PTSD improve associated symptoms (e.g., depression), romantic partner distress, and couple relationship satisfaction? Participants will participate in a two-day retreat in which they are taught and practice skills to decrease PTSD symptoms and enhance their relationships. Researchers will compare AIM-CBCT for PTSD to the Prevention and Relationship Education Program (PREP) to determine whether it is superior to an evidence-based relationship education curriculum that is also delivered in a two-day multi-couple group format.

Inclusion Criteria: * Service member or veteran and a romantic partner willing to participate. * Couple is married or cohabiting for at least 3 months. Couple can be either different or same sex. * Service member/veteran diagnosis of PTSD as determined by the CAPS-5. * Each partner is at least 18 years old. * Both partners able to speak and read English. Exclusion Criteria: * Either partner reports current suicidal ideation severe enough to warrant immediate attention * Current homicide risk meriting crisis intervention for either partner * Current and severe alcohol misuse in either partner warranting immediate intervention * Symptoms of moderate to severe other substance use warranting immediate intervention * Recent (past month) manic episode or psychotic disorder symptoms in either partner * Other psychiatric disorders severe enough to warrant designation as the primary disorder * Evidence of a moderate or severe traumatic brain injury or other cognitive impairment in either partner * Couple is separated or have taken steps to dissolve their relationship * Either partner is currently participating in evidence-based treatment for PTSD (e.g., Prolonged Exposure, Cognitive Processing Therapy, Present-Centered Therapy for PTSD, Eye Movement Desensitization and Reprocessing, Cognitive-Behavioral Conjoint Therapy for PTSD, or Structured Approach Therapy). * Evidence or admission of severe intimate aggression by either partner occurring within the past 6-months.