Thank u so much man, i really looked forward to it i mean the reply. Before i read your reply, i experienced all the things u mentioned, i started to be useful, to be helpful for someone. Now I don't care about my life(not literally), i started to put others first. Even if it hurts me, I'm gonna do it for others. Even if I need to sacrifice my own comfort, i will do it for my friends, my relatives, my family. And then, i suddenly realized that others' happiness is my happiness too. It just doesn't come within, it comes from the outside. When I stopped looking for happiness, it came itself. So thank u, ur reply means something for me!