knowing someone

there's a time..
there's a time when you feel that you know your friends or people around you inside outside.
you feel that you know them very well. you know everything about them, from a to z.
you said to everybody that you know their habit and you claim that they are your best bud and you know their secret.

but the fact is,

everybody has secrets, even the dark ones. the ones that they want to keep it privately.
there will be something that you won't know. and just let it as a secret.

everybody has their own thoughts, their own decisions.
kita bisa bilang kalau kita bakal tahu keputusan orang terdekat kita, karena kita merasa mengenal mereka. tapi, apakah selalu begitu?
ada kalanya kita mendapatkan kejutan dari orang tersebut.

apakah itu karena kita "kurang mengenal" orang tersebut?
apakah itu karena semua orang dengan mudahnya berubah?