Mary is the Mother of God if Jesus is divine . It is really a formula arising from the Christological controversies of the 4th and fifth Centuries.
Jesus wasn't divine. He was a hippie who rebelled against a bloody and oppressive government. As a result, he convinced other hippies to follow him, until the Roman government made him a dead hippie. Then the others turned it into a hippie cult that would have gone nowhere if Emperor Constantine hadn't embraced it. Constantine shaped Christian beliefs 300 years after Jesus was a dead hippie on a stick.
Jesus preached peace and love, and if he were alive today, conservatives would trash him as a kooky liberal pacifist.