I agree that it seems like lecturing, especially the second paragraph when you used the word "mistake" about 20 times. She will not want to be told it was all a big mistake. Let her save face by thinking it was all totally justified at the time, and now, she is making a new decision, not taking back the old one.
Make it a lot shorter and get the points you really want to get across: that you love her, and that you send her good wishes in her decision making (and will accept whatever she decides). Keep the pressure off at all costs.
