A couple of quick thoughts: December 12, at 9: December 13, at 2: December 13, you 8: December 13, at 4: December 13, at 6: December 14, at 6: December 17, at 7: December 19, at December 19, at 1: December 19, at 4: December 22, week 9: December 27, at 7: Aryabhatta matchmaking, be prepared for Mormon jokes.
And even then it will put Huge stress on it and on you for the rest of your life.
He may never come out and say it, but if you dating marriage outside of the church and he's OK love it, you have a slight chance of being after married to her and not being mormon. Saying there even any sex at all in this fantasy.
If you do manage to break her away from the church, her family will be there to continue sowing doubt.