"The Catholic Church has sanitized Mary. They make it a sinful thing for even a married woman to engage in "carnal" activity." This statement was made by a professor in a wonderful course I took in college called "Religion and Truth."
The professor was a visiting dean from Trinity College in Ireland.
He spoke about the Church's attitude towards women and sex and talked about the awful Magadalene Laundries, a place of punishment for young village girls in Ireland. They were sent there by their parish priests for "acting interested in sex." There was a documentary on the laundries and the stories of the survivors were heart-wrenching.
He said that the Church made Mary celibate in marriage and a virgin. No woman could live up to her ideal, not even a married woman. Thus all women were sinful.
Professor O'Leary believed that Mary did have children by Joseph. He said that sex is seen as sinful by the Church as a means of controling women.