Advanced technologies not only produce external transformations in society but also elicit significant emotional responses in individuals. Immersive psychological technology, which leverages the cognitive effects of Extended Reality, Artificial Intelligence, and Virtual Twin Avatars, is the methodology adopted by SITh (Self-Insight Therapy), based on Gestalt psychotherapy—a therapeutic approach emphasizing ‘here-and-now’ awareness and ‘human-in-the-loop’—serves as a prominent example. This study presents a case study of XR-based mourning ritual service leveraging immersive psychological technology to support bereaved family members in coping with grief after a tragic aircraft disaster in South Korea in December 2024. The findings illustrate how technology can facilitate safe third-party intervention in the grief recovery process for individuals who have lost family members. The XR-based mourning ritual case study, combined with an interview with a bereaved family member, indicates a promising direction for advancing traditional healing methods through immersive psychological technology integration.