If Mary is the Mother of God and mothers preexist their offspring then Mary preexists God. I don't see the problem for saying this since I have been accused of Nestorianism for declaring Mary is mother of Jesus.
What you said was "Mother of Christ is fine,....". That's "Christotokos", which is exactly and precisely Nestorianism. If you want to be a Nestorian, that's fine with me. I thought that heresy had died out about 1600 years ago, but these discussions with you champions of Protestantism have taught me that many of the old heresies are alive and well.
Remember these words (I assume you do recite these words somewhere in your services)?
"And in one Lord, Jesus Christ, the only begotten Son of God, begotten of the Father before all ages. Light of Light, true God of true God, begotten, not created, of one essence with the Father, through whom all things were made.
For us men and for our salvation, He came down from heaven and was incarnate by the Holy Spirit and the Virgin Mary and became man."
Next time you recite the Creed think Theotokos, Blogger, not Christotokos. If you can't do that, don't mock the Creed by reciting something you don't believe.