<human>: Can you provide a brief rundown of the text in within 3 sentences?

I'm in a bit of a tough spot here. I've never liked one of my fiancée's good friends, the girl is selfish, self-centered, rude, and generally an "all eyes on me" sort of person. We've discussed it, and my fiancée understands that I don't like her and why I don't, and agreed that I would never have to spend time with her. Here's the problem, our wedding is coming up and I don't want this girl there because I feel rather certain that she'll do something that will ruin the night. My fiancée understands how I might think she will act up, but still wants her there anyway. I've never got along with this girl and I don't want her to be a part of our day. If she does act like her normal self, it will be a disaster and my (at that point) wife will be upset,  but at the same time,  she'll be upset if she's not there. I've been tasked with making this decision and I don't know what to do.
<bot>: Fiancée's friend is terrible, I don't want her at the wedding, she does, wants me to make the decision