So you're saying Jesus isn't God? Because if Mary is the Mother of Jesus, then she must be the Mother of God. I suppose you accept the incarnation as a mystery, but will not accept the mystery of Mary's motherhood of God? Why?
Mary gave birth to the man Jesus - the only begotten of God
The "man Jesus" is not the only begotten of God. The Son - the Word of God - is begotten of God. Jesus is the Word made flesh, begotten of the Virgin Mary and her spouse, the Holy Spirit. But here's where it gets tricky: Jesus is BOTH the only begotten of God - as the Divine Word - AND the offpspring of Mary. Since Jesus IS God, then Mary IS the Mother of God. It's a mystery. Just like God taking on the flesh. How did He do it and remain at His eternal throne? We don't know. It defies logic and science, but it happened. How is Mary the Mother of the Eternal God, if she herself is a mortal? It's a mystery, but she is.
Nowhere does Scripture instruct man to separate Jesus' human and Divine natures, for any purpose whatsoever. The Church, however, believed from the outset that Mary was not some ordinary soul outside of her being created. Since God Himself tells us that "all nations will call [her] blessed," who are you to complain?
correction: “all generations will call me blessed,” not “nations”.
As God, Jesus has no earthly parents. He was and is the second person of the God head, ever existent. Born in the flesh as a man. That human form was given birth by Mary - not the Lord Jesus. He - Jesus - was before Moses ever drew breath.