Noooo... That's my initial response, sorry. It feels a bit done. I've read that one before.
Try something less obvious, like "Please don't read this book. You're going to think I am insane, and if I die, I don't want people to remember me as crazy, and I'm sure everyone will think I am after they have read this. You're still reading, aren't you? Well, then you should know that I am actually not insane, and I am not a liar either. The things written here are true, even if no one believes me."
I don't know. That might be bad too, haha! Keep working on it, if it's done right, it could be really dramatic!