Dean,

I can feel it, you know. Every night you wake up thrashing, in a cold sweat, the scream in your throat dying down just as it's about to leave your lips every time you dream of Perdition and I wanted to say I'm so sorry. So sorry I can't be there to take you in my arms and rock you back to sleep, crooning in your ear "It's alright, everything is alright," even when it's clearly not. Sorry I can't be there to harp on about how much I miss the old Impala too and most of all, I'm sorry I can't be there to witness those rare moments when you can actually smile and be happy despite the absolute shit the world's going to, because I know they must be few and far between. But I think of you every passing moment, and although maybe it hurts that I'm not around right now, if I had the chance to do it all over, I wouldn't hesitate, not for a moment, to die all over again to make sure you lived.

Maybe it may not seem like it was all that worth it now but I can tell. I know you have more to live for than it feels like now because you, Dean Winchester, are amazing. And if there's one thing I know you're capable of, it's beating the odds. You may not believe me, but trust me, and I know I haven't always given you the best reasons to be, but trust me when I say an angel always knows.

I always did adore you, and every awkward moment of invading your personal space under the pretense of being that clueless, socially inept angel was simply another excuse to be as close to you as I could. When I held eye contact with you, every second I did was like a shock to the system, electrifying in the most seductive way. It was subtly intoxicating to even be in your presence, and I didn't even realise it until I was already addicted, spiraling deeper into the dependence everyday with no hope of recovery, and just as well because I don't want to be. You are a drug, my amortensia, so potent it hurts. But it's a sweet sort of torment. You have me in the throes of Elysian agony and it hurts so good.

It kills me a bit more inside every day to think about how I'll most likely never see you again, never lock gazes with those clover green eyes, eyes that when aimed at me felt like they saw through to a place no one else had ever been and understood. You were the only human I had ever met who had identified so much with every hardship I had endured, and for every time your eyes lit with acceptance and understanding of why I did some of the things I did, even if you may not have agreed with them, my gratitude was more than you could have known.

I know this is never going to reach you but I can't help thinking that maybe that profound connection we shared is somehow still strong enough that you can at least feel that someone, somewhere is thinking of you, wondering about you, loving you because I do. More than I probably should. And I hope that in that knowledge you can take some solace. I love you, Dean. You will always be my beloved mortal, my hunter, the one human I couldn't stand and cared far too much for.

Yours come Hell or high water,

Castiel