I would say to her, "I am filling the dog dishes and the coffee pot. It is not my intention to leave your mug unfilled, nor is it my responsibility to read your mind. Next time you want water, just ask me in advance and I'd be happy to oblige. Otherwise, you'll be thirsty."
Get a little harsh with her, buddy!
She acts like a crabby princess and gets away with it, thus feeding that beast.
Every time you stand up to her, she respects it and responds favorably..
