25 The consequences of this evil have been thus described by Pope Leo XIII, in words whose truth is incisive: "Because of divorce, the nuptial contract becomes subject to fickle whim; affection is weakened; pernicious incentives are given to conjugal infidelity; the care and education of offspring are harmed; easy opportunity is afforded for the breaking up of homes; the seeds of discord are sown among families; the dignity of woman is lessened and brought down and she runs the risk of being deserted after she has served her husband as an instrument of pleasure. And since it is true that for the ruination of the family and the undermining of the State nothing is so powerful as the corruption of morals, it is easy to see that divorce is of the greatest harm to the prosperity of families and of states" (Encyclical Letter Arcanum ).
Source: Sertum Laetitiae (Vatican.va)