I remain utterly convinced that Mary Magdalene and Mary of Bethany are the same person. The four Gospels all contain the account of the anointing, and the details make it clear that these all refer to the same event. In St. John 12:1-11, the person anointing is identified as Mary of Bethany. In the other Gospels, the woman is not identified by name, but she is recognized as "a sinner." In two of them Mary Magdalene is named as one out of whom Jesus had driven seven demons. The Lucan account of Mary and Martha may even be the occasion on which this took place.
So Mary's anointing of Jesus for burial is token of her love, and her love is the result of his abundant mercy shown to her. Her story is the story off all Christendom. The sermon.