Despair is a word one associates with the tragedy of a person taking their own life, and I have known some who have taken the final action. So to drill down, does lack of meaning cause despair, I presume it does. I agree that 'people' are one's greatest resource and that is why group therapy can be a dynamic force. If one takes Alcoholic Anonymous (and its many 12 step spin offs) its success lies in imparting purpose and by association meaning though example. Neurologically in group therapy our 'Mirror Neurons' operate where as in isolation they don't.