How to Stop Longing for Someone You Know Is Impossible This report targets the phenomenon of compulsive emotional dependence and pathological limerence triggered by an 'unavailable object'. Grounded in neurobiology, attachment theory, object relations theory, and psychopathological mechanisms, it systematically deconstructs the addictive nature, etiological roots, and clinical diagnostic criteria of this psychological phenomenon. The report deeply integrates evidence-based psychological intervention strategies including Cognitive Behavioral Therapy (CBT), Dialectical Behavior Therapy (DBT), and the Internal Family Systems Model (IFS), and constructs a full-process clinical rehabilitation program from radical boundary setting, disenfranchised grief mourning, to cognitive structure restructuring, underlying trauma healing, and core identity reconstruction. It aims to help individuals break free from the neural hijacking of the dopamine reward circuit, and complete systematic psychological healing from emotional exhaustion to the reclamation of life sovereignty.