Pain, pain was the one and only thing Castiel felt searing through his used and damaged body. There was a time Castiel thought he liked the pain: he thought he liked it because he thought he deserved it. But this? This was too much for his fragile heart to take. Ever since he became human, everything had taken its toll on Castiel. The fact that he'd went behind Dean's back to do dirty work with Crowely, or the fact he went as far as breaking Sam's mind to rescue his own ass. Or maybe when he consumed all the souls to defeat Raphel but then decided to abandon his only fellow friends. Furthermore in the course of his actions he went on to devastate heaven and obliterate all of his brethren because he thought he was doing the right thing. Just like he thought he was doing the right thing when he made his brothers and sisters suffer more when he cast them all out of their home, causing most of them insanity and pain. He'd always thought he was doing good. Yet Dean so happens to remind him frequently that everything he does is never - not ever - good.
The feeling of warm tears trickling down ones cheeks was something Castiel grew to hate: crying was a sign of weakness in most of their eyes, so when a salty stream slides down his face, hitting the floor silently, he could just wished his problems would fall away with his tears. Or the tightness you get in your throat, like your heart is trying to ram itself up there and force its way through your mouth, almost like you're choking. The knots in his stomach when he doubles over in pain from the amount of crying and the amount of alcohol he consumed is yet another thing he hated. Thoughts swarmed Castiels head as he took another swig from the bottle of God knows what he was drinking. He didn't really know what it was, but he learned from Dean that when something was wrong, drinking until you couldn't see straight was effective. Yet No amount of drinking could make him forget how much of a failure he was heaven and Earth, the Winchesters and his siblings. He saw it all coming really, every time he drank he saw the pain that would follow, yet he still did it. A failure was all he was. He was broken. The words bounced around his head and flowed through his blood stream and left through a grumble through his mouth. Broken.
The words fit too well in his state, and they fell too perfectly off his lips each time he muttered them bitterly. Broken. He was like a jigsaw puzzle with all the wrong pieces and because of that, he would be thrown away after a while because he was useless and expendable, broken, like shattered glass that was too sharp to touch and only held destruction in its wake, broken. The tears flowed quicker now, hitting the floor at a steady pace while his heart beat quickens with the amount of alcohol he was consuming. A strangled sob escaped its way out of his throat and he barley had time to silence himself. But silence himself he did: with another swig of the toxic liquid that burned the back of his throat with every swallow. The more he forced down his throat, the more the fiery pain of the burn satisfied his darkest needs.
But it seemed the weeping of this fallen angel attracted unwanted attention because Dean stood at the frame of the door, looking down at his companion. A thousand emotions flickered through his emerald green eyes as he puzzled the pieces together of his broken friend. Pain? Shock? Guilt? Pity? Disappointment? Castiel didn't know but before he had a chance to register what was happening, a mutilated cry left his lips: "Nobody cares that I'm broken, Dean." With that he had finally understood the mess he'd become, and the fear drowned him. He didn't even have control over what he was saying. His half drunken state let the words freely sway from his mouth. He wanted to call out for his beloved hunter but all he could do was stare in utter horror as he was slowly consumed by the monster he had become.
Deans action came as a shock to him as he almost flung himself at the distressed angel on the ground: He swooped him into his arms and cradled him. Holding him tight, tight enough to hold all his broken pieces back together and with that Castiel's shaky hands slowly snaked their way over his body and clung to Dean like his life depended on it; As if he was in a sea slowly drowning to be lost forever but Dean was his lift raft to raise him from perdition. Pitiful cries wrecked his body, shaking him through to the core as he buried his head into Deans shoulder.
"I care that you're broken, Cas"