What Is the Name of This Book? question

Okay, I am going to provide all of the details I can about this book, but I loved it when I was younger and I cannot for the life of me remember it. The details I do know: a young girl in high school who joins the Quiz Bowl team. She has a crush on this one guy but soon becomes close with the guys cousin who's name I believe is Max. They form a friendship that develops into more. Her grandma has a stroke, and I know the main character has some trauma with water and drowning, leading to a falling out with her and Max because he tries to get her to swim and she falls into the pool. I know there is also a book/coffee shop where they all hang out and maybe a mention of a Rocky Horror Picture show. Please help!!!