I wouldn't go so far as self-righteously telling someone what their purpose in life is. Besides that, if you want to go down that road, being in a support class

I wouldn't go so far as self-righteously telling someone what their purpose in life is. Besides that, if you want to go down that road, being in a support class and being a productive, supporting member of society in other ways is an evolutionarily valid position. Perhaps someone views their life's purpose to support close family, even if they can't have any kids, or their definition of family may be much more abstract and inclusive to a larger community. Perhaps they do what they do for humanity rather than for themselves alone.