Psychoanalytic theory, with its move away from drive theory to object-relations, lacks a compatible model of the power of psychosexuality in adult life (including in therapy). It is proposed that in infancy drive tension, frustration and urgency may be erotized by the caregiver; while actual sexual excitement may remain unmirrored and uncontained. This produces a psychosexual core which is unstable, elusive and never felt to be really owned. In sexual acts we can project and identify with our own sexuality, felt to belong to the other, yet allowing more successful re-internalization and gradual integration. The relief at being able to relate to troubling aspects of the self, via the other, creates a deep attachment bond, although sexual excitement may fade as self-integration becomes more secure. The technical challenges of working on sexuality in long-term, relationship-focused psychotherapy with an implicit parental model are briefly considered.