Dear Emelia Fenchurch,
I came across this quote in a book once and it said, "Everyone is a little crazy. The only difference between us and them is that they hide it better." Perhaps your friends just want to talk lowly about your world in attempt to cover up or deny their own. I think everyone makes up ideals in their heads about how they wish things could be, and I don't think you are insane for doing that.
I daydream all the time about made up scenarios. And I get teased for believing that mythical creatures are actually real. No matter what, someone is going to think we are crazy, so you might as well do what makes you happy. If your friends are real friends, then they'll get over it and accept you. Anyway, sane people are boring.
Oh! I just remembered. If you want to get away for awhile at school, I know of a very friendly ghost named Anya. She floats around in the abandoned classroom on the 4th floor. She won't judge you. She's great! And if you decide to talk to her, make sure you tell her I say hello!
Eybdoog (that's goodbye backwards. Anya and I use that as a farewell)!