Here is what the Catholic Encyclopedia has to to say:
http://www.newadvent.org/cathen/09761a.htm
St. Mary Magdalen
Mary Magdalen was so called either from Magdala near Tiberias, on the west shore of Galilee, or possibly from a Talmudic expression meaning "curling women's hair," which the Talmud explains as of an adulteress.
In the New Testament she is mentioned among the women who accompanied Christ and ministered to Him (Luke 8:2-3), where it is also said that seven devils had been cast out of her (Mark 16:9). She is next named as standing at the foot of the cross (Mark 15:40; Matthew 27:56; John 19:25; Luke 23:49). She saw Christ laid in the tomb, and she was the first recorded witness of the Resurrection.
The Greek Fathers, as a whole, distinguish the three persons:
the "sinner" of Luke 7:36-50;
the sister of Martha and Lazarus, Luke 10:38-42 and John 11; and
Mary Magdalen.
On the other hand most of the Latins hold that these three were one and the same. Protestant critics, however, believe there were two, if not three, distinct persons. It is impossible to demonstrate the identity of the three; but those commentators undoubtedly go too far who assert, as does Westcott (on John 11:1), "that the identity of Mary with Mary Magdalene is a mere conjecture supported by no direct evidence, and opposed to the general tenour of the gospels." It is the identification of Mary of Bethany with the "sinner" of Luke 7:37, which is most combatted by Protestants. It almost seems as if this reluctance to identify the "sinner" with the sister of Martha were due to a failure to grasp the full significance of the forgiveness of sin. The harmonizing tendencies of so many modern critics, too, are responsible for much of the existing confusion.
The first fact, mentioned in the Gospel relating to the question under discussion is the anointing of Christ's feet by a woman, a "sinner" in the city (Luke 7:37-50). This belongs to the Galilean ministry, it precedes the miracle of the feeding of the five thousand and the third Passover. Immediately afterwards St. Luke describes a missionary circuit in Galilee and tells us of the women who ministered to Christ, among them being "Mary who is called Magdalen, out of whom seven devils were gone forth" (Luke 8:2); but he does not tell us that she is to be identified with the "sinner" of the previous chapter. In 10:38-42, he tells us of Christ's visit to Martha and Mary "in a certain town"; it is impossible to identify this town, but it is clear from 9:53, that Christ had definitively left Galilee, and it is quite possible that this "town" was Bethany. This seems confirmed by the preceding parable of the good Samaritan, which must almost certainly have been spoken on the road between Jericho and Jerusalem. But here again we note that there is no suggestion of an identification of the three persons (the "sinner", Mary Magdalen, and Mary of Bethany), and if we had only St. Luke to guide us we should certainly have no grounds for so identifying them. St. John, however, clearly identifies Mary of Bethany with the woman who anointed Christ's feet (12; cf. Matthew 26 and Mark 14). It is remarkable that already in 11:2, St. John has spoken of Mary as "she that anointed the Lord's feet", he aleipsasa; It is commonly said that he refers to the subsequent anointing which he himself describes in 12:3-8; but it may be questioned whether he would have used he aleipsasa if another woman, and she a "sinner" in the city, had done the same. It is conceivable that St. John, just because he is writing so long after the event and at a time when Mary was dead, wishes to point out to us that she was really the same as the "sinner." In the same way St. Luke may have veiled her identity precisely because he did not wish to defame one who was yet living; he certainly does something similar in the case of St. Matthew whose identity with Levi the publican (5:7) he conceals.
If the foregoing argument holds good, Mary of Bethany and the "sinner" are one and the same. But an examination of St. John's Gospel makes it almost impossible to deny the identity of Mary of Bethany with Mary Magdalen. From St. John we learn the name of the "woman" who anointed Christ's feet previous to the last supper. We may remark here that it seems unnecessary to hold that because St. Matthew and St. Mark say "two days before the Passover", while St. John says "six days" there were, therefore, two distinct anointings following one another. St. John does not necessarily mean that the supper and the anointing took place six days before, but only that Christ came to Bethany six days before the Passover. At that supper, then, Mary received the glorious encomium, "she hath wrought a good work upon Me . . . in pouring this ointment upon My body she hath done it for My burial . . . wheresoever this Gospel shall be preached . . . that also which she hath done shall be told for a memory of her." Is it credible, in view of all this, that this Mary should have no place at the foot of the cross, nor at the tomb of Christ? Yet it is Mary Magdalen who, according to all the Evangelists, stood at the foot of the cross and assisted at the entombment and was the first recorded witness of the Resurrection. And while St. John calls her "Mary Magdalen" in 19:25, 20:1, and 20:18, he calls her simply "Mary" in 20:11 and 20:16.
In the view we have advocated the series of events forms a consistent whole; the "sinner" comes early in the ministry to seek for pardon; she is described immediately afterwards as Mary Magdalen "out of whom seven devils were gone forth"; shortly after, we find her "sitting at the Lord's feet and hearing His words." To the Catholic mind it all seems fitting and natural. At a later period Mary and Martha turn to "the Christ, the Son of the Living God", and He restores to them their brother Lazarus; a short time afterwards they make Him a supper and Mary once more repeats the act she had performed when a penitent. At the Passion she stands near by; she sees Him laid in the tomb; and she is the first witness of His Resurrection--excepting always His Mother, to whom He must needs have appeared first, though the New Testament is silent on this point. In our view, then, there were two anointings of Christ's feet--it should surely be no difficulty that St. Matthew and St. Mark speak of His head--the first (Luke 7) took place at a comparatively early date; the second, two days before the last Passover. But it was one and the same woman who performed this pious act on each occasion.
Subsequent history of St. Mary Magdalen. The Greek Church maintains that the saint retired to Ephesus with the Blessed Virgin and there died, that her relics were transferred to Constantinople in 886 and are there preserved. Gregory of Tours (De miraculis, I, xxx) supports the statement that she went to Ephesus. However, according to a French tradition (see SAINT LAZARUS OF BETHANY), Mary, Lazarus, and some companions came to Marseilles and converted the whole of Provence. Magdalen is said to have retired to a hill, La Sainte-Baume, near by, where she gave herself up to a life of penance for thirty years. When the time of her death arrived she was carried by angels to Aix and into the oratory of St. Maximinus, where she received the viaticum; her body was then laid in an oratory constructed by St. Maximinus at Villa Lata, afterwards called St. Maximin. History is silent about these relics till 745, when according to the chronicler Sigebert, they were removed to Vézelay through fear of the Saracens. No record is preserved of their return, but in 1279, when Charles II, King of Naples, erected a convent at La Sainte-Baume for the Dominicans, the shrine was found intact, with an inscription stating why they were hidden. In 1600 the relics were placed in a sarcophagus sent by Clement VIII, the head being placed in a separate vessel. In 1814 the church of La Sainte-Baume, wrecked during the Revolution, was restored, and in 1822 the grotto was consecrated afresh. The head of the saint now lies there, where it has lain so long, and where it has been the centre of so many pilgrimages.
