shadow of a self

Lately I feel like I've lost heart. I honestly don't know what my problem is. I guess I don't know where I'm going in life right now or what to do, so maybe I lack purpose. But that can't be all. I feel like a shadow of the person I really am, and I'm not sure what to do about it. I know all the right answers, but I think it's waiting now for something to click. I don't like feeling sorry for myself and struggling to make it through each day. I want to live every moment for God, being the person He has made me to be. So why can't I just do it? Honestly, I don't know what to do with myself.