There's lots of supposition about her and we know very little. The only sources we have which inform us about Mary Magdalene are the gospel texts and suppositions which are clearly made up, for example.....people have called her a prostitute. In the bible they never used the Latin word pornae to describe her, so clearly there is no evidence she was a prostitute.
There are three Mary's in the Gospels whos stories have been merged into much of the Magdalene "narrative". A pious development due to this confusion is that she was the woman who washed Jesus' feet. This popular image of Mary Magdalene comes from confusion between her and two other women: Martha’s sister Mary and an unnamed sinner in Luke’s gospel (7:36-50). Both of these women wash Jesus’ feet with their hair. It didn't help that Pope Gregory the Great declared that all three women were the same person.
On a slight side note however...... mainstream Christianity holds that Jesus was a sacrifice, and as such in the Jewish Tradition a Sacrifice would have needed to have been anointed, and as Myrrh was used for anointing the dead it makes sense to anoint and prepare him for death in that way.
This anointing could indicate a more mystical role for a woman called Mary who performed this act, but there is no evidence it was Mary Magdalene. Traditionally such anointing would only be performed by an Initiated Priesthood, hinting that this woman was possibly some kind of Sacerdotal Priestess who prepared the Christ for the Crucifixion.
This in itself could have significantly deeper meaning. In the writings of Theosophists like H.P. Blavatsky, C. W. Leadbeater and Annie Besant we encounter the theory of involution and evolution. That Divinity descends and enters matter and then evolves back out of it for a whole host of reasons which could be explored in another post.
C. W. Leadbeater in his works 'Christian Gnosis' and 'The Christian Creeds' suggests that Genesis (Gen. 1:2) - the Spirit moved across the face of the deep - is an allegory for the stage before this descent into matter. That the Spirit which "moved" across "the deep" was the Spirit preparing matter for it's reception of Divinity. Leadbeater also holds that by limiting Itself in space and time the Christ would have undergone a process which would have caused it to experience great suffering. Leadbeater goes on to state that this was the true "crucifixion" the descent of the Divine into matter. The descent into the deepest parts of creation could be seen to be being illustrated when we are told that Christ passed through death and descended into Hell. Following death the body would have been anointed with oils. It could be argued that this anointing with oil, by the woman, was both to prepare him for his death and for the sacrifice at the same time. This echoes what we find the Spirit doing in Gen. 1:2.
In Esoteric (Gnostic) Christianity it is often held that the Spirit is Feminine. This is significant as the Spirit moving over the deep prepared the way for the Christ to descend into matter. Then a woman once more, prepared Christ for the next stage of the journey which then resulted in the universal salvation of all things by giving them divine consciousness, even if not at the surface level but at some level within their beingness.
So what's my point in all this......there's SO much nonsense being put out by New Age Guru's and conspiracy theorists concerning Mary Magdalene that it's hard to say what is or isn't true about her and what she may or may not have done. Even what is written here is only "one" possible interpretation of the text and it could be completely wrong. What is interesting however, is that many people use the composite story of Mary Magdalene to draw out allegorical truths, to empower women, to find occult truths and to find deeper meaning in the gospel narratives.
Now I know some of you will come back at me with the Gospel of Philip and what it may or may not say.......all I can say to that is that the document has large holes in the text and we have no way of concretely establishing fully what it is saying about anything. In addition it was written significantly later than any of the other Gospels and so it's hard to accurately gauge it's value.