I totally understand your frustration and anger. My feelings would have been really hurt if I were in the same situation.
The wedding is over now, so I just say let things go. If you still feel the need to discuss this with her, send a note or e-mail. Thank her for coming and spending all of the $$$ to attend. Tell her you understand her situation but were disappointed and hurt by her behavior, you felt like all that mattered was him, not you or her BM obligations. Say you were frustrated and embarrassed having to answer to your other guests about her behavior and disappearance.
Chances are this relationship will not last and she will come crawling back to you once she wakes up and realizes she acted like an idiot. My guess is she knew she was in the wrong and that is why she reacted the way she did. To play devil's advocate, she might have felt abandoned with you getting married - stupid I know, but I had a friend totally shut me out right before the wedding.
I think if you say what you need to say to make you feel better, then that is all you can do. It will then be up to you to decide if you want her to be a part of your new life.
Good luck!