Believers are immune to the depression consequent upon purely material upheavals. 
We must shake off depression and go forth to proclaim the gospel with great energy, never forgetting that Jesus was with us throughout our season of discouragement, and will continue with us to the end. 
The words to Fortune, the young downcast, were: “My friend, arise! Stand up like a man! Your mind should be your courageous ally in the solution of your life problems rather than your being, as you have been, its abject fear-slave and the bond servant of depression and defeat”. 
Thomas the apostle was afflicted by depression. When he was most depressed, unfortunately he always tried to avoid coming in direct contact with Jesus.