Mary's level of esteem in the Catholic church can be overwhelming and confusing. We have statutes and stained glass windows dedicated to her. We have an entire set of prayer beads dedicated to her intercession, she's obviously a big deal.
But Mary, as mentioned earlier, was born and raised by loving parents and was given a choice by God, just like us. It is her willingness to go where God called her to go that helps set her apart from the other saints. Once Mary had conceived, she still tried to remain faithful to God. She was told to visit her cousin, Elizabeth, and did so gladly, which is now known as the Visitation.
Mary's love and devotion to God makes her unique in our "Hall of Fame" because she was so purely human but still the perfect vessel to carry and raise God's own Son. We truly believe that because Mary gave birth to and raised Christ, who was both fully divine and human, that Mary is the Mother of God. She, just like our mothers, carried us to term, gave birth, and then loved and raised us. What could be more understandable than the relationship between a mother and her son. God understood that we would struggle to believe in and pray to something we could never truly understand. The parental relationship between Mary and Jesus, so reflective of our relationship between us and our Creator, helps us to better understand what God offers us.
Mary has become so much to us in the Church but before that she was just a young girl and then a young mother who said "yes" to God.