That's really kind of ridiculous, sorry. She wasn't "before God," nothing "came before God," and no Catholic with a second-grade-or-better knowledge of their faith thinks otherwise.
But she was, and is, the Mother of God because Jesus is truly God and she truly became his mother. To deny that is to deny the Incarnation, and to become, well, like the Muslims.
I most certainly do not deny Jesus’ incarnation. What I deny is the strong implication in the title “mother of God” that Mary birthed or came before God. Yes, she is the mother of Christ who is God but she did not give birth to His “Godness” she gave birth to His person hood.
The Son was always God thoughout eternity past. Only God can attest to always existing. He became Jesus the son of Mary at a certain place and time in the history of mankind, which was something completely new. The title “mother of God” may cause many Catholics to be confused about who she is as many Catholics do worship her. Maybe you do not. I hope not. That does not mean that many others do not.