The Trauma of Betrayal: Treating Adjustment Disorder With Reconsolidation Blockade Under Propranolol

Inclusion Criteria: * Diagnosis of an adjustment disorder or chronic adjustment disorder, as defined by the Diagnostic and Statistical Manual for Mental Disorders, as a result of an attachment injury, defined as an event involving the perceived betrayal, violation of trust, or abandonment by a significant other. * Currently experiencing clinically important psychological distress as a result of the event, as defined by a score of at least 22 on the IES-R, and a score of at least "moderately ill" on the Clinical Global Impressions - Severity of Illness Scale. * Must have been in the romantic relationship for at least 6 months prior to the event. * Must not take psychotropic medication. * Fluency in English or French Exclusion Criteria: * Systolic blood pressure \<100 mm Hg; * Cardiac rhythm below 55 beats per minute; * A medical condition that contraindicates the administration of propranolol, e.g., Asthma, chronic obstructive pulmonary disease, cardiac insufficiency, cardiac choc, Second- or third-degree atrioventricular block, diabetes, spastic angina, auricular sinus illness, bradycardia, Raynaud's disease, severe peripheral vascular disease, untreated Pheochromocytoma, arterial hypotension, previous anaphylactic allergic shock; * Previous adverse reaction to, or non-compliance with, beta-blocker; * Current use of a substance that may involve potentially dangerous interactions with propranolol, including P450 2D6 inhibitors. * Women who are pregnant or breast feeding; * Individuals currently participating in any other form of psychotherapy (other than strictly supportive). * History of substance dependence disorder, bipolar disorder, or psychotic disorder; * Participants judged (based on history, mental status exam, clinical impression, or the Suicidal Behaviors Questionnaire as being at significant risk of suicidal behavior. * Participation in another drug trial within 30 days prior to the screening visit * Presence of any clinical condition that might interfere with the interpretation of the efficacy and safety results.