Abstract: Adaptive persona — the capacity to shift social presentation across contexts — is a defining feature of identity architecture, yet its psychological costs remain undertheorised. Drawing on Goffman's dramaturgical model, Hochschild's analysis of emotional labour, Higgins's self-discrepancy theory, and Winnicott's account of the false self, identity performance is not the corruption of selfhood but its normal operating condition — and cost accumulates not through performance itself but through the widening gap between performed and experienced self. When that gap crosses the coherence threshold, persona management ceases to function as a cognitive skill and becomes a source of sustained depletion. Institutional selection pressures drive this breach systematically. WHO burnout classifications and McKinsey workforce evidence confirm the cost at scale, while authenticity research adds a productive complication: the damage profile is modified by whether performance is chosen.