Please post the chapter and verse references where the term *mother of God* is found in the Bible.
Check Luke, please. The Visitation to Elizabeth.
I think it's strange that any Christian who knows any theology at all would object to "Mother of God". It's pointing directly to Jesus' divinity and attesting to it in undiluted form. It's rejecting all the heresies against it -- Arianism (Jesus is not really God), Adoptionism (Jesus became God after birth, because God liked him), Nestorianism (there's a Jesus who's God, and a Jesus who's man, and they're sort of co-located and always seen together), Docetism (Jesus is an appearance of God, not really flesh and blood), etc.
Do you hold to an orthodox Christology, or not? Is Jesus both truly man and truly God, 100% of both, from the first instant of his conception in Mary's womb -- but still a divine, not human, person, who existed as God-the-Son from all eternity?