Life?

What does it mean to truly live? This has been frustrating me beyond belief, and I get more and more annoyed with it everyday. There's this quote in Tsubasa where Sakura's bunny dies, and her father tell her there is no way to bring back the dead. He tells her, "That is why life is so precious. Because you don't have forever to live."
I'm currently reading a book that expresses this quote. Charlie St Cloud is all but dead, holding on to the past and never thinking about the future. I don't really know what the author intends to do so far, except to define what living is. So, what is living? What does it mean to live instead of survive? Why does it drive me crazy that I feel I am not living? It's almost like a box, a giant box that consists of invisible, but stone walls that cover every bit of risk away from the prisoner inside. Then there's this simple feeling nagging in the back of my mind that I'm not doing what I want. Instead, I do what others expect me to do and then I just sit there and wait until my mind bursts and won't shut up when it's time for me to rest. It's almost like I feel alone or stuck in some sort of self-inflicted rut of immobility.
I'm an observer, instead of a doer, and i think I may be starting to realize that I was never an observer. I pretended to be in order to protect myself from risks and stay in a comfortable, but mind numbing, ironic cycle of annoying routines that have nothing to do with me. More and more I stare at the door, window and any possible out from this invisible tower. But what else is annoying me? Why am I always writing question after question and getting more frustrated with every question I can't answer.
So, who am I? And, what do I want? Where do I stand between the wallflower I am clearly not, and the social person I used to be?