Sam wasn't an idiot. He noticed when his brother zoned out with horror in his eyes, when he jolted awake at night, gasping for breath, sweating and fighting back tears. He noticed when Dean became more withdrawn, even though it seemed like he was trying to be his normal sarcastic self.
But being close to Dean wasn't easy. Especially when it came to things like how he felt. Sam knew Dean preferred to deal with things on his own, but that didn't make it easy for him to sit and watch his brother suffer more each day.
Each incident merged with the next, and each day Sam noticed a new piece of his brother slipping away into the abyss. But there was always one time that stood out in Sam's mind like a sore thumb. It was early in June, and Sam was coming back to the motel they were staying at, burgers and fries in tow. When he opened the door, he was immediately greeted with a sombre sound of sobbing. Not just a light shedding of tears, but full on, heartbreaking sobbing.
He located the sounds in record time, forcing the bathroom door to see Dean shaking and crying on the floor with his head in his whole body was trembling and he was breathing in shallow gasps, clearly worked up about something.
It took a lot of time to convince Dean to share what had happened, but when he did, he uttered a quiet "I can't do it anymore Sammy, oh god help me Sammy" before collapsing into his brothers arms and letting himself go for a while longer. They stayed like that for the best part of an hour until Dean had calmed enough to let Sam know about all of the thoughts, every nightmare, every time he came close to making dreams a reality. Once he started, he just didn't stop.
Sam just sat and let him talk, occasionally whispering reassurances into his brothers ear. He wanted to let Dean know he was listening, but part of his silence was purely out of shock. He'd never seen his big, strong brother like this. Not even after the fire.