Ok here's my two cents.
Growing up, I've had 9 close friends die before I hit the age of 19. Not including family, etc. After about 5 I finally realized it's a given. People die.
You'll eventually learn that it's life. Everyone dies, you will die, your dog, your TV, your car, etc.
Learn to accept it.
I don't mean you have to be a goth, or get depressed etc. Just remember it's life. There isn't one living thing in the entire history of our world and time that hasn't had to deal with death and then die itself.
I will, you will, Ashlee Simpson will, and everyone else.
Relax, drink a beer, and watch Family Guy. We've all been there. It's no biggie. It's life.