There is a classic moment in 'The Sun Also Rises' when someone asks Mike Campbell how he went bankrupt, and all he can say in response is, Gradually and then suddenly. When someone asks how I lost my mind, that's all I can say too.
Prozac Nation: Young and Depressed in America (ed. Houghton Mifflin Harcourt, 2014) - ISBN: 9780547524146