This document discusses morbid jealousy and its subtypes. It defines jealousy as a negative emotional response to a threatened relationship, and morbid jealousy as an unfounded preoccupation with a partner's infidelity. Morbid jealousy can be delusional, involving false beliefs despite evidence, or non-delusional, involving obsessions and compulsive behaviors. Theories for its development include psychodynamic, cognitive, and social factors. Assessment considers diagnoses like delusional disorder or obsessive-compulsive disorder. Treatment focuses on underlying psychopathology through psychotherapy and medication management.