21.09/4.09

absence |ˈabsəns|nounthe state of being away from a place or person : the letter had arrived during his absence |• an occasion or period of being away from a place or person : repeated absences from school.• ( absence of) the nonexistence or lack of : she found his total absence of facial expression disconcerting. See note at lack .
if absence makes the heart grow fonder, then why am i so scared of feeling empty ?missing my best friends is such a strange emotion, i don't really feel that you can define "missing' someone as readily as "absence of" or "lacking something/someone".