How healty or un is it to believe that the sun rises and sets just for you and that you are the center of everyone's universe? Why?

I wouldn't know.  I never felt that way, but they say true narcissists see the world like that.  

It is highly mentally ill and totally sociopathic.   You'd better be smart and a great manipulator because it will take a lot of energy to be successful with these qualities or lack of them.   You will be dead inside, and missing all the great gifts being empathetic and kind and loving and caring and social will net you.   You will have to spend all your time alone, even when socializing with hundreds of people because no one thinks like you except OTHER sociopaths who are only thinking of themselves and could care less about you.

I have been in Center of the World, Ohio. It is very small and located near Youngstown, Ohio. It is sometimes called 'Center World, Ohio.'  (Google it)