Mary is another great hero of our faith. She was an humble servant. But she is not the Humble Servant. Mary, as we see in the story and song of Luke 1 was a woman that God used for His purpose and plan.
We have mis-taught Mary. We've looked up to her in ways that have an outcome in the ugly false gospel of moralism. Moralism robs us of the opportunity of being used by God too because moralism results only in the guilt of "Me? I could never be used" or the deception of pride "Me! Look at me."
This isn't how Mary was used. And it isn't how Mary felt about being used. Instead she rejoiced in God her Savior and was glad in how He used her for His glory and her enjoyment.