10 There are also some who strongly maintain that priests by reason of their celibacy find themselves in a situation that is not only against nature but also physically and psychologically detrimental to the development of a mature and well-balanced human personality. And so it happens, they say, that priests often become hard and lacking in human warmth; that, excluded from sharing fully the life and destiny of the rest of their brothers, they are obliged to live a life of solitude which leads to bitterness and discouragement. So they ask: Don't all these things indicate that celibacy does unwarranted violence to nature and unjustifiably disparages human values which have their source in the divine work of creation and have been made whole through the work of the Redemption accomplished by Christ?
Source: Sacerdotalis Caelibatus (Vatican.va)