The aim of Shared Decision Making (SDM) is to provide information to patients in order to enable them to decide autonomously and freely about treatment together with the doctor, without interference, force, or coercion by others. Relatives may be considered as hindering or impeding a patient’s own decision. Qualitative-empirical research into lived experience of SDM of patients with cancer, however, problematizes the patient’s autonomy when facing terminal illness and the need to make decisions regarding treatment. Confronted with this difficulty, this contribution tries to think through patients’ dependency of others, and make their autonomy more relational, drawing upon care-ethical critics of a one-sided view of autonomy and upon Ricoeur’s view of the fundamentally intersubjective, relational self. We aim to conceptualize relatives not as a third party next to the doctor and the patient, but as co-constituents of the patient’s identity and as such present in the decision-making process from the outset. What is more, partners and the family may be of inestimable help in retrieving the patient’s identity in line with the past, present and possible future.