I have supashort hair and I love it - I think it's sexy and I look like nobody better give me any shit :-D It's way easier to take care of, it's easier to dye, and everyone who matters thinks it's sexy. And frankly I don't look that good with longer hair - it's fine and tangles easily, and doesn't like to stay put up in any kind of "do" and won't hold a curl.
Thank the people who tell you how much better you'd look with longer hair and tell them cheerfully that they could use some concealer, or that they'd look a lot better if they lost 10 pounds