It's always necessary to know when a stage of one's life has ended. If you stubbornly cling to it after the need has passed, you lose the joy and meaning of the rest. And you risk being shaken to your senses by God.
From the greatest to the smallest, happiness and usefulness are largely found in the same soul, and the joy of life is won in its deepest and truest sense only by those who have not shirked life's burdens.