With the rapid development of the metaverse and immersive technologies, virtual experience has emerged as a pivotal innovative medium, significantly enhancing user participation and fostering profound emotional connections. Grounded in Symbolic Interaction Theory and Self-Expansion Theory, this study investigates the mechanisms through which virtual experience interactivity influences user acceptance and attachment. The research framework posits three dimensions of interactivity—content interaction, situational interaction, and device interaction—as independent variables, with user acceptance and attachment serving as dependent variables. Furthermore, self-cognitive expansion, spiritual expansion, and self-efficacy expansion are incorporated as mediating variables. Data were collected through an online questionnaire survey, yielding 350 valid responses from active users of various virtual platforms. The data were subsequently analyzed using Structural Equation Modeling (SEM). The empirical results demonstrate that all three interactivity dimensions significantly impact user acceptance and attachment, but through distinct mediating pathways. Specifically, situational interaction strongly influences attachment through the mediation of self-cognitive expansion, while device interaction directly drives user acceptance. Content interaction, on the other hand, exerts its primary effect on attachment via spiritual expansion. These findings not only validate the theoretical model and enrich academic research but also offer valuable practical insights for designers and marketers seeking to optimize virtual experiences.