I found a few websites that explain pretty well what Catholics believe about Mary (and the Saints). In my words… we ask Mary and the Saints to “pray for us” the same way we would ask a friend or relative to pray for us. So, we aren’t praying TO Mary and the Saints but instead asking them to pray WITH us. This makes sense to me.
However, I also found a website that articulates beautifully why Catholics so deeply revere the Virgin Mary:
Mary is the Mother of God. Catholics do not believe that God was bound by any compulsion to have a Mother; they believe that He chose to have a Mother and all that this implies. He chose to permit His human body to be formed in her womb.
I love the line about God not being bound to have a Mother… that he Chose to have a Mother and that by so choosing, gave a Mother to the human race like none we had ever had before.
Hail Mary, full of grace, the Lord is with thee;
blessed art thou amongst women,
and blessed is the fruit of thy womb, Jesus.
Holy Mary, Mother of God,
pray for us sinners, now and at the hour of our death.