Have you ever?

Have you ever felt like a zombie?
Where you do not know what you want exactly.
Where you will grab anything when you are walking in a hypermarket and pay it at the counter.
Where you eat but do not know what is the taste of the food like.
Where you have no expression when you are watching something funny.
Where you are merely faking yourself in front of your friends.
Where you just nod your head when your friends are talking to you.
Have you?