"Dead" "aLive!!!" "Life !!!"

Live your life!!! How to tell if someone is alive? Does someone without dreams, hope and future consider alive? Even if a person does have a dream but didn't have the courage fulfill it, does he/she consider alive? A person who does not hope for anything in life, he/she consider alive? What if a person without a future? How should people live their lives? Live for their own or for someone else? Why do some people live for someone else? Some live for the sake of the dead? Some live for the sake of the living? Some live for the sake of what? Read, asked and saw many things for the past 17 years, still cannot figure out what I want in Life and what is the true definition of life. Don't know why but I fear of..........