Living Dead

I often wonder if I am truly living. What does it mean to be alive? As I feel numb more often than not, I am not sure. I even question if I actually exist, or if I am just some figment of someone else's imagination. Is that weird? I'm human, but I don't feel real. I am just some ball of mass floating around with no purpose other than to survive. But why? Why struggle so much to get by when breathing hurts most of the time? Wouldn't it be easier to let the current take me away? Should I just sink down to the depths of the earth and not return? I wonder this all too often.