Uncomfortable at Halloween party, what should I do?

I live in London, and I am a writer. About a year ago, I went on a Hellenic cruise, and met a woman there, Judith Butler. We became friends, and she invited me to stay with her. She's a widow. She's got a daughter, a girl called Miranda who is twelve or thirteen. They live in Woodleigh Common. Some friends of hers were giving a Halloween party, for children, and she said I should come, and perhaps I had some interesting ideas. Frankly, I was not much of a help. There was that woman, Rowena Drake, she was so efficient, she organised everything, competition for the best decorated broomstick, cutting the flower cake, arriving of Halloween, girls looking for future husbands in the mirror, bobbing for apples, this kind of thing. They had a supper, too, rich iced cakes, savouries, prawns, cheese and nut confections. It was a success, really, but I felt very much out of place. I went to the bathroom, and there was a couple of teens making up, pressed against the door, and I had to ask them to leave, and they were so indignant about it. And then there is this girl, Joyce, who keeps talking about my books, and how "The Dying Goldfish" was not good, because there was not much blood in it (I write detective stories), and then she started talking about how she had seen a real murder, when she was "quite young". I think she is a morbid teen, who is showing off, and I do not like her. Yet I have to stay on till this party ends, who knows when, what should I do?