Today mental health professionals are challenged in supporting people with severe mental illness that live within their communities. The community treatment is, however, characterized by an uncertainty about how to best support them in their everyday lives, and professionals from different disciplines often have divergent opinions about the care. The aim of this study is to explicate the existential meaning of living with severe mental illness. Interviews with persons who relocated from an institutional setting to a community placement were analyzed within an interpretive approach. The results of the study found that people with severe mental illness experience an existential loneliness due to difficulties in changing previous suppositions about human relationships. They do not develop connections through shared new experiences with other people in their lives. One central implication of the findings is that because people with severe mental illness seem unable to benefit from new experiences, mental health nurses should consider relational aspects when planning, implementing, and evaluating nursing care.