I was a pretty boring person before, so I'm still boring now, lol. I don't drink, but since I never did my friends are just used to it. My fiance loves it because I can always drive.
I DO go out every weekend though and I did during my weight loss. You can't shut yourself away from the world!
I make sure to get in exercise and eat right around all of this. It isn't terribly hard if you're not afraid to be a bit vocal about the places you want to go, but even now most places have healthier foods. Then again if you don't eat your whole meal you're generally fine if you choose an "unhealthy" option.