I am now all alone in this world.
I had to stand around, watching all of my friends die, trying to help, but knowing there was nothing I could do.
Some long to be Angels, to have wings to shield others from harm. They are all yet to realize that wings are good for nothing except inflicting pain upon one's self. If I had the chance, I would have given up being an angel long ago.
But with heaven still in pandemonium, there was absolutely nothing anyone could do about anything. So I will continue to be a hunter.
No more Sam, no more Dean, no more Bobby, no more anyone. I am lost and forgotten by all except myself.  Everyone I have ever known or loved are long gone, all the lost ones.
Every time I ever tried to settle down, get a job, and run away from the hunting life, it came back and found me. I have lost count of how many times I have failed attempting to save an innocent soul...the demons and beasts and spirits and monsters that roam this world always win.
So why do I continue doing what I do? Same reason the Winchesters did.
Saving people, hunting things, the family business. Dean always said I was almost part of the family. Well now I guess I really am a Winchester.

I am Castiel Winchester, the lost angel.