Quote from : Swann's Way Book

... was the great and general renunciation which old age makes in preparation for death, the chrysalis stage of life, which may be observed wherever life has been unduly prolonged; even in old lovers who have lived for one another with the utmost intensity of passion, and in old friends bound by the closest ties of mental sympathy, who, after a certain year, cease to make, the necessary journey, or even to cross the street to see one another, cease to correspond, and know well that they will communicate no more in this world.