The discussion focused on how individuals with borderline personality disorder (BPD) often transform their intimate partners, even mentally healthy ones, into narcissists through a dynamic of unstable internal and external object constancy. It was explained that borderlines struggle with maintaining stable internal representations of others, leading to chaotic behaviors and emotional dysregulation, which drives partners to withdraw and develop internal objects representing the borderline, mirroring narcissistic dynamics. This cyclical interaction produces mutual avoidance and approach behaviors, perpetuating a complex and destructive relationship pattern where both parties exhibit traits of narcissism and borderline pathology. Borderline’s Partner: Some Enter Healthy, Exit Mentally Ill (Starts 12:10)