I have a cousin who’s something of a mean girl. We’re the same age, and most of her comments to me seem competitive or jealous or both. I usually just avoid her, but recently I got engaged. She used to work for a wedding planner before she had a baby. Now she’s decided that she’s going to help me with my wedding. I’ve both politely and bluntly made excuses for why I don’t want her help, but my aunts have all decided this is great and dismiss every excuse I make. She’s already started with some nasty commentary regardless (apparently, she thinks my fiancé is ugly). Is there a way to shut this down entirely without saying, “I don’t want to deal with you because you’re obnoxious”?