importance, from where?

How much importance should i get? From whom? Generally if i don't get expected importance from a person, it disheartens me.
So always try to keep 0% expectation from any body. But don't know how, in my mind, may be i always want some importance.
Coz when i see people who think about me and come to me in their bad times, then they forget about me in their happy times. it hearts. Trying to take it easy. I shouldn't expect anything from anyone. But don't know, may be my absent mind wants a lot.....