“ Sometimes a man or a woman is made a great deal better and happier in the end for having had to conquer the faults of the one beloved, and make the fitness not found at first, by gradual assimilation. There is a class of good women who have no right to marry perfectly good men, because they have the power of saving those who would go to ruin but for the guiding providence of a good wife. ”
 Oliver Wendell Holmes Sr., The Professor at the Breakfast-Table (1860). copy citation

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“The idea that in this world each young person is to wait until he or she finds that precise counterpart who alone of all creation was meant for him or her, and then fall instantly in love with it, is pretty enough, only it is not Nature's way. It is not at all essential that all pairs of human beings should be, as we sometimes say of particular couples, “born for each other.” Sometimes a man or a woman is made a great deal better and happier in the end for having had to conquer the faults of the one beloved, and make the fitness not found at first, by gradual assimilation. There is a class of good women who have no right to marry perfectly good men, because they have the power of saving those who would go to ruin but for the guiding providence of a good wife. I have known many such cases. It is the most momentous question a woman is ever called upon to decide, whether the faults of the man she loves are beyond remedy and will drag her down, or whether she is competent to be his earthly redeemer and lift him to her own level.” source