For example, the church father Jerome vigorously argued marriage as being inferior to virginity and celibacy. Others such as Athanasius and John of Damascus taught that the concept of marriage was derived from original sin. Augustine thought that it was impossible to engage in marital relations without also having ungodly lusts. Basil claimed that although he personally rejected the teaching, many in his day believed in the perpetual virginity of Mary.
After centuries of christological disputes, the Second Council of Constantinople officially declared the mother of the Lord Jesus Christ to be "ever virgin."
Perhaps another source which sparked the development of Roman Catholic Marian theology was the small Arabian cult known as the Collyridians, which appointed woman to be priests so as to offer sacrifices of bread to Mary. They worshiped her, and also believed her to be a perpetual virgin.
Additionally, it would be wise for one to consider this excerpt from the late second to mid third century scholar Origen:
“And depreciating the whole of what appeared to be His nearest kindred, they said, Is not His mother called Mary? And His brethren, James and Joseph and Simon and Judas? And His sisters, are they not all with us? They thought, then, that He was the son of Joseph and Mary. But some say, basing it on a tradition in the Gospel according to Peter, as it is entitled, or The Book of James, that the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honor of Mary in virginity to the end.” (Commentary on Matthew, 17)
Notice how the catechism of the Roman Catholic Church defends the perpetual virginity of Mary:
"Against this doctrine the objection is sometimes raised that the Bible mentions brothers and sisters of Jesus. The Church has always understood these passages as not referring to other children of the Virgin Mary. In fact James and Joseph, "brothers of Jesus", are the sons of another Mary, a disciple of Christ, whom St. Matthew significantly calls "the other Mary". They are close relations of Jesus, according to an Old Testament expression." (CCC # 500)
Thus, we see that Roman Catholic apologists have resorted to apocryphal literature in order to substantiate their claims. Even the Roman Catholic New American Bible makes it crystal clear that Mary did not remain a virgin her entire life:
"He had no relations with her until she bore a son, and he named him Jesus" (Matthew 1:25)