Everything was different since he got Sam back. That was expected. Dean knew it would be a struggle for things to ever go back to "normal", or whatever amount of normal they could ever reach again. He didn't know to expect this.
Sam was silent again. He refused to talk, curled into himself in the corner, staring with wide eyes into the empty room.
"Sam," Dean said again. Sam did not react. He sat beside his little brother. "Can you hear me?"
Sam's breathing was shallow and quick like he was in danger. He would take in a random, ragged gasp of air and then return to silence.
"Sammy, I don't know if you can hear me, but it's okay. I'm right here," he took a hand and set it slowly, gently on Sam's knee.
The reaction was instantaneous. Sam leapt forward, banging into the wooden coffee table with his forehead. He hit the ground and writhed like he was trying desperately to escape something, but it had caught him and he couldn't get away. He cried out as he thrashed. "Stop, stop, stop. I'm sorry. Please stop," he wept. Dean's heart cracked in his chest.
"Sammy, please, it's me," Dean implored, but Sam didn't stop. Dean tried again to touch his shoulder, but it set him off worse than before.
"NOSTOPHELP," he stilled. Tears welled in Dean's eyes. Seeing his little brother like this tore him apart. Sam shouldn't be in this much pain ever. He was too fragile, too young, too good. "Dean," Sam whimpered.
"I'm here," he placed his hand next to Sam, not daring to touch him, and hoped he would reach out. He didn't. He laid, whimpering and childish, and through the night they sat there until he finally fell asleep.
Dean picked up his little brother and carried him to the spare bedroom. He was always thin, but now he was bony and weighed almost nothing. He laid him in bed and pulled the covers over him. His hair was a mess from rolling on the floor. Dean sat beside him and tenderly smoothed his hair out, then continued to pet his head. Sam let out a soft sound and nuzzled into Dean's hand. Dean leaned down and kissed him on the forehead.
Sam sat quietly at the breakfast table while Dean cooked. That was how Sam did everything now. Quietly. He walked around the apartment like a ghost. It had surprised Dean on more than one occasion. He barely spoke and when he did, it was soft and nervous. He never raised his voice to speaking level. Dean didn't ask himself why he acted any of the ways he did. He didn't dare wonder why Sam was so afraid of being heard. It wasn't that he didn't want to know what happened to him. It was that he couldn't. It would break him. This was already testing him, and he didn't think he could handle more.
Dean finished the scrambled eggs and toast and put them down in front of Sam. Sam eyed them. "Gonna eat, kiddo?" Dean asked. Sam peered up at him with a pale face. "Don't feel like talkin' right now?" he sat down across from him and ate his own meal, hoping that it would encourage Sam. His little brother picked at his plate between glances at Dean. "You know you're safe, right?" Dean asked.
When Sam stopped moving the food around on his plate, Dean cleaned up. Sam waited to be told what to do, or else he would simply stay put in the same spot all day. Dean learned to move him around the apartment or to instruct him to do simple tasks to keep him occupied. "You're gonna watch some cartoons," Dean told him. He turned down the lights and left him in the living room while he pulled out his computer and started working at the breakfast table.
It had been a long time since Dean hunted. He sometimes felt guilt about not hunting, but he had a different purpose now. He had someone else to save. The sacrifice was never in the question. He would give up whatever he had to in order to help Sam. That meant not a lick of anything supernatural in the house. No books, no paraphernalia, no talk of it, absolutely nothing.
After a couple hours passed, Dean came back to the living room to check on Sam. "Do you need to use the bathroom?" he asked. Sam offered a small shake of his head. Dean saw tears flash in his eyes through the thin light. "What's wrong, Sammy?" he still asked, even though he never got a reply. He sat down on the couch beside Sam. Against all expectations, Sam grabbed his hand. Dean gasped.
"Dean," Sam said, voice still small, but significantly louder than he had spoken so far. He opened his mouth to talk, but instead shoved his head into Dean's chest.
"Woah," Dean said. Sam gripped the front of his shirt like he might get dragged away. He hugged him desperately and cried with heaving shoulders into his chest. It took Dean half a moment to recover from the shock before he wrapped Sam in his arms. He thought Sam may bolt, but he remained anchored.
"Dean," he managed between sobs.
"I'm right here. I'm here," he rubbed circles on Sam's back.
"Is this real?"
Dean was concerned with the question. Had he been hallucinating? "This is real."
"B-because I thought it was real before, but it wasn't. It was a trick."
There was another crack somewhere inside Dean, but he would put his heart back together later. "No tricks here. Just me."
"I didn't think I would get to leave. I didn't think I'd get to see y-you-" he deteriorated into sobs once more.
"I'm sorry I wasn't there for you. I'm sorry I couldn't save you. I'm here now. No one's going to hurt you again. You're okay. I'm right here," he murmured as he pet the back of Sam's head.
"I was so scared."
"I know," Dean could only imagine from what he saw here, the vestiges of the torture that Sam had endured. He was petrified every second of the day. Whatever happened to him… Dean stopped himself from delving further into the thought. "You don't have to be scared anymore."
"I'm sorry. I'm sorry. I'm sorry."
"No sorry. Don't be sorry. You're doing great. I'm so proud of you."
"You are?" Sam stopped to look up at his brother.
"Of course. It's hard right now, but it won't be forever. You're going to be okay," saying it out loud was maybe the first time that Dean truly believed the words, "You're going to be okay," he repeated, "You're safe."
"I'm safe," Sam whispered, tentative eyes lovingly observing Dean like he was the one thing in the world that he could trust.