It sounds like the existential depression in gifted described here:
http://www.sengifted.org/articles_counseling/Webb_ExistentialDepressionInGiftedIndividuals.shtml

P.S. This book has more info how existential depression is tied to Dabrowski's theory of positive disintegration and advice that may help.
http://www.amazon.com/gp/search?index=books&linkCode=qs&keywords=0910707898

Last edited by inky; 02/25/11 02:55 PM. Reason: P.S.