I'm still at school, and only one of my pets has died so far- a guinea pig that I had had for almost seven years. It really wasn't too sad when he went- I'd been prepared for it for ages, and he went out really peacefully and all. I shed a single tear, bid him farewell, and headed off to school that day- I was sad, but not devastated- the little guy had had a good life.
When my family dog dies, however, I don't see myself dealing with it so easily. It's still at least 5 or 6 years away from happening though, so I'm not worrying about it too much at the moment...