When the angel Gabriel appeared to Mary and told her that she would be the mother of the Messiah, she was honestly surprised that God would select someone like her.
Though Mary was a virtuous woman, she was not a sinless woman. Mary was a sinner just like us. Privileged? Yes. Called by God? Yes. Sinful? Again, yes. Later, in what has been called the Magnificat, or Mary's Song, she said, "My spirit has rejoiced in God my Savior" (Luke 1:47). Even Mary needed a Savior.
When people are truly godly, they never boast of their devotion. They will not speak of what they have done for God. Rather, they will always speak of what God has done for them. That is why John described himself in his gospel as the disciple whom Jesus loved. John boasted of God's love for him rather than his love for God.
Had Mary been like many other young women of her time, she would have married a poor man, given birth to numerous children, and wouldn't have traveled more than a few miles from her home. Then she would have died like thousands of others before her, another person who entered and left the human stage. But God chose her, despite the fact that Mary was a nobody living in a nothing town in the middle of nowhere.
Mary was handpicked to fulfill prophecy: "Therefore the Lord Himself will give you a sign: Behold, the virgin shall conceive and bear a Son, and shall call His name Immanuel" (Isaiah 7:14). I seriously doubt that Mary, in her wildest dreams, ever read that verse and thought, That is me. I'm going to be the virgin Isaiah spoke of. I'm going to be the mother of the Messiah.
God can use you where you are.