Today it is hardly possible for any group to remain so isolated from others who have different values. Therefore it is necessary today for the individual to find support within himself. . . This strength within himself—through access to his own real needs and feelings and the possibility of expressing them—thus becomes crucially important for him on the one hand, and on the other made enormously more difficult through living in contact with various different value systems. These factors can probably explain the rapid increase of depression in our time and also the general fascination with various groups.
Alice  Miller, The Drama of the Gifted Child: The Search for the True Self
community, depression, identity