She became a nun After High School.
Convents or orders of nuns or “sisters” usually change the names of the members to depict the change that has happened in their lives. Since formerly they were living in a secular state, these celibate Christians (like the apostles who’s names were changed by Jesus) now wish to take on a new identity as Christ-followers. Many have compared it to taking a new name at marriage.
Part of this name change, in Catholicism, almost invariably involves taking on the name of Mary, mother of the Lord, and the remarkable “woman” first mentioned by God in the Book of Exodus when he prophecied how salvation would finally come about:
Genesis 3:15 And I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel."