Castiel had lived a long time, occasionally he'd heard people talking sometimes joking, most times not about angels.
One particularly crisp autumn evening two brunettes were sitting on a bench in the park Castiel was playing in just talking in general about life when one girl's story came up.
"Ya I heard her best friend died just the other day." The first brunette stated sipping her coffee.
"Mhm and on top of that her house caught fire and she found out her boyfriend was a no-good cheater." The second one added.
"Man, and angels think they have it bad." The first said a bitter laugh escaping the confines of her mouth.
Castiel never thought of it again until after God had left the world, when angels had free will, and after he'd betrayed his friends. He then recalled the conversation and thought about how similar humans and angels were now, with the ability of free will of course.
He started thinking that brunette who had just been bitter and slightly cruel might have known what she was talking about. Maybe they did have it worse off, they did have to constantly choose between good and bad, deal with interfering emotions, and free will was, he was now realizing, a shitty thing to have. It sucked, no one told you what to do, no one said this is your purpose go do it now. No, you were expected to find these on your own!
What an impossible task! Castiel had thought before reconsidering it. In all actuality, it wasn't impossible because clearly humans made some sense of it and most got along just find making, or following the right path in their lives.
Still, what did they know they were just human, and so Castiel, angel of the Lord was introduced to the complex, infuriating, rewarding world called Freedom.