"Going to the chapel, and your gonna' get married........."
You may have to be really hard lined with her and tell her to stop. I have had to do this once or twice. My dad didn't want to come to my wedding, and it shows on his face in all of the pictures. I hope he decides that we wants to be there when his son gets married, but if he really doesn't don't let it get you down. He'll have to live with it- you just enjoy the day with the love of your life!