This thesis examines the process of adjusting to a relative’s dementia, as the illness profoundly transforms and alters daily life, the material organization of living spaces, domestic routines, marital and filial relationships, and modes of interaction. The social experience of the illness is explored through the prism of the sociology of socialization, focusing on the individual dispositions and competencies that shape how people conceptualize the illness, engage with their relative, perceive their role as a caregiver, adapt to new circumstances, and reorganize everyday life. These adjustments can be reinforced or redefined over the course of the illness trajectory through ongoing socializations that develop as part of the long-term caregiving process and through interactions with various actors encountered along the way, including medical professionals, social care workers, volunteers, and peer groups. The last two decades have been marked by the deployment of multifaceted support services for caregivers (respite care, disease-specific training, psychological support groups, etc.), aiming to assist families in avoiding psychological and physical exhaustion. These resources frame the illness experience differently, depending on how caregivers engage with, appropriate, or distance themselves from these supports. They may converge with, conflict with, or reshape the practical adjustments made by families. The analysis is based on the longitudinal follow-up of caregivers’ experiences over several years, observations of caregiver support services (respite care, caregiver training programmes, mobile Alzheimer’s team, psychological support groups, etc.), and statistical analysis of data from the ‘Capacités, Aide, et Ressources des seniors’ (CARE) French surveys. The thesis thus shows how, through the interplay between prior socializations and those currently ongoing with their relative who is affected by Alzheimer’s, families take on long-term caregiving responsibilities with varying levels of ease and transform, to different extents, their perspectives on the world, the illness, their relative, and themselves.