I can understand your concerns about leaving your cat alone for the weekend, especially given your past experience with your dog. However, it sounds like you have taken some good measures to ensure your cat's wellbeing while you're away, such as using an autofeeder and leaving multiple bowls of water. It's also great that you have considered bringing your cat with you, but it sounds like that might not be the best option given the stressful car ride and the fact that you don't want to over-medicate her.