Here is are a nice pair of passages from Thornton “Wilder”
….”He divided the inhabitants of the world into two groups, into those who had loved and those how had not. It was a horrible aristocracy, apparently, for those who had no capacity for love (or rather for suffering in love) could not be said to be alive and certainly would not live again after their death. They were a kind of straw population, filling the world with their meaningless laughter and tears and chatter and disappearing still lovable and vain into thin air. For their distinction, he cultivated his own definition of love that was like no other and that had gathered all its bitterness and pride from his odd life. He regarded love as a sort of cruel malady through which the elect are required to pass in their late youth and from which they emerge, pale and wrung and ready for the business of living…. at least they never again misunderstood and mistook a protracted amiability for the whole conduct of life, they never again regarded any human being, from a prince to a servant, as a mechanical object…..
…”This assumption that she need look for no more devotion now that her beauty had passed proceeded from the fact that she had never realized any love save love as passion. Such love, though it expends itself in generosity and thoughtfulness, though it give birth to visions and great poetry, remains among the sharpest expressions of self interest. Not until it has passed through a long servitude, through its own self-hatred, through mockery, through great doubts, can it take its place among the loyalties. Many who have spent a lifetime in it can tell us less of love then the child that lost the dog yesterday.”