Past Lives (2023) is widely read through diaspora, temporal rupture, paths not taken, and unrealized possibilities. This study argues that such readings require a sharper distinction between the self-Nora Moon actually experienced and the adult self that might have formed if her biography had unfolded differently. Using theory-guided qualitative cinematic close reading, this article brings together possible selves, alternative selves, and counterfactual thinking with film analysis. The analysis examines dialogue, temporal ellipsis, spatial bifurcation, mediated communication, relational framing, and audiovisual withholding. The findings indicate that childhood Nora provides prospective material in the form of literary ambition and rudimentary relational self-projections, not a pre-formed alternative adult self. Migration and divergent life courses alter the attainability of this relational trajectory, while the adult reunion with Hae Sung reconstructs it retrospectively through questions about what might have happened if Nora had never left Seoul. The film distinguishes Na Young as the actual past self from the alternative adult Nora, who never existed in the actual storyworld. This counterfactual adulthood becomes narratively specified but audiovisually withheld. The ending can therefore be read as mourning without reversal, an acknowledgment of an unrealized possibility without repudiating Nora's actual life. This study demonstrates how audiovisual withholding makes counterfactual identity perceptible without making it actual.