Serious mental illness is a neurobiological condition that qualifies as a disability. We pay taxes so that people with debilitating disabilities, unable to work and earn wages for self-sufficiency, can live lives of dignity. You and your ill friend or relative should use the disability benefits to which you are entitled.
Many a family has tried to support an adult child with mental illness until the child is 30 or 40, at which time all retirement savings have been exhausted and the family is financially destitute. Mental illness is a disease which can, and does, bankrupt families. This often happens because the person with mental illness is unable to work and must be supported by their parents for continued daily living and medical support.