Let me take the first shot.....It is my experience that although this is all very nice, it probably means very little in the grand scheme of things. Believe me, I know the feelings that such an encounter brings on. That is some nice goodwill on your w's part. You need to do the same...not to win her back but simply to show her that you can be friends. That should be your first goal. Don't go into all the reasons why you can not, just do it. Be civil, be accomodating, be nice just like you would with a friend (yes i know friends don't do what she did to other friends). Try to take this as day one ... a nice gesture...nothing more, nothing less.