Castiel was not too far off when it came to his assumption of Dean's whereabouts. He was sitting in front of Sam. Head in hands, and he was stewing about the recent turn in their relationship. Only, not in a way that would have made Castiel feel confident in the future of this budding romance.

"Dammit, Dean! For Chuck's sake. (The brothers had long since stopped calling the creator of the universe God after they officially met the Chuck Taylor wearing deity on a suburban street during one of the many apocalyptic events they became embroiled in). You have been in love with the guy almost from the day he walked through that barn door." Sam turned away from his brother frustrated. Dean had just spilled his guts to Sam about everything that had been chewing him up on the inside when it came to his feelings for Cas. Concluding with the last night's romp on Dean's memory foam bed, and Sam was now in the unenviable position of helping his brother deal with his horrible case of the morning after "what have I done?" regrets. Sam first order of business was to stop Dean from going into too much detail about the hook-up. Then he had to assuage the guilt and worry his brother felt about the change in his relationship with the guardian angel.
Before Cas' accident and the ensuing emotional self-evaluation. The angel had been held at arm's length, by Dean's infamous wall. A wall fortified with bricks formed from stubbornness and mortared together by fear.
So Sam knew he had to show Dean why Cas was worth his dropping his guard to allow Castiel in.
"Stop worrying about everything else going on or could go on and just let yourself be happy." Sam had pulled a couple of beers, and after cracking them both open, he handed one over to his irritatingly anal brother. Sam smiled inwardly at the inside joke that he just made. Taking the seat across from his morose sibling, Sam looked into tired green eyes and said "Go. Be with Castiel and forget all of that other crap you were worried about. You deserve this... this thing you have with Cas." Sam paused as if looking for the right words. Sighing with exasperation, he continued; "Dean, he is the only one who can help you shoulder all the shit that comes our way..."

Dean opened his mouth to interrupt, to refute Sam's assertion that Cas was the only one strong enough to help Dean. Sam cut him off. Knowing what his overly protective brother was going to say about Sam being more than capable too, but Sam had to make Dean understand how it was different; "Look, Dean. I am not saying that you don't think I can handle myself in a fight with whatever ghoul we go up against, or that I won't have your back in every one of those fights. But when it comes to what you need" Sam put extra emphasis on the word 'you' to get Dean's attention; "Dean, when you need to step away and just be...be normal or...or whatever! You need someone you can be intimate with, who you can turn to and share yourself with. Someone, like Cas, who understands what we do every day and more importantly. How it affects you" Sam tilted his head downward, his brow creasing as he brought his eyes back up showing his best puppy dog look. Dean quickly turned his gaze away. Pretending, badly, to be distracted by the picture that has hung over the kitchen sink so long the stained outline of the frame is part of the backsplash. "You need someone like Cas, and despite what you think, he is strong enough to share that burden. Cas is a freaking angel and" Sam bobbed his head a little trying to force Dean to look back and meet his eyes. He continued when green eyes finally came around to meet his with some humor creeping into his voice said, "when he isn't getting himself hurt and does have his powers, Cas is a force to contend with but more importantly. He is someone you can share your thoughts and fears. Because with me you feel you can't always tell me what you feel and as your younger brother. I get that. I understand why you can't always be honest when it comes to opening up to me. You will always try to protect me, Dean. And it's because of this mindset of yours that you need someone with whom you trust as much as you trust me. You need Cas. He is your best friend, and I can see he is so much more to you than that now. And it is okay."

Dean stared at his younger brother, and it was as if he were looking at him for the first time. Jokingly, he muttered to himself "Well, look who is all grown up?"
Sam set his mouth in a grim line. Frustrated at his brother's sad attempts at deflecting the honest emotions coming from his argument.
Using his beer as a more successful delay tactic, Dean took a pull of the cold amber liquid and contemplated his reply as he began to pick at the label corner. Everything Sam had just said was the truth, and Dean fought with himself as he struggled mentally to admit out loud to Sam that he is right. Finally, with some effort and a voice filled with conviction Dean replied; "Sam, I...I don't know why or how it happened, but I just know that it did. Somewhere along the way, Cas became a part of our little family, a...and I found myself caring for him and every time he took a hit for us. I felt that I had to protect him too, so I decided I wasn't going to let him in, I felt I had to push him away. Because I was terrified of what I was beginning to feel inside." Dean stopped and flicked a bit of label from his finger. "And back when I kicked him out of the bunker to save you. It nearly tore me in two." Dean paused. The air between the two brothers became tense. Dean swallowed hard and took another drink from his beer. Then in a whisper, he continued "You see, Sam. I wanted to keep him with me." Dean looked up into Sam's eyes and when he did Sam's heart nearly broke. He remained silent waiting for Dean to continue; "For the first time I had to make a decision between you and Castiel and for the briefest of moments, I came so close to keeping Cas because I wanted him to stay with me. Because of how I felt about him." Dean's eyes were no beginning to well up at the memory and with a voice raspy with sadness "And it would have killed you. And I was horrified that I almost did that." Dean continued to peel the label from his beer as he continued "So that is when I told him to go and when all was said and done. After Gadreel was gone, and things had more or less gotten back to normal, only Cas was now human...ish. I knew I couldn't let my feelings get in the way ever again. So I put away what I felt, or I thought I had..." Dean stopped. Sam debated whether finished for him but decided to let his brother figure it out on his own. As the seconds stretch on, Sam feared Dean had chickened out and was about to go silent. Throwing all of the progress made so far out the proverbial window and as Sam began to open his mouth to say something, Dean continued with more determination in his voice; "Even now I am terrified of what is going to happen. So I feel like I need to go in there and tell Cas that everything was a mistake and that we shouldn't do this" Dean swirled his hand in the air for emphasis "That we should just stay friends and that he should stay away from me and that I need to stay away from him. I don't think I could stand to see him hurt by me again and I am afraid that I might someday."

"You don't mean that Dean," Sam said softly

"I don't know Sam, we came close to losing each other a hundred times, but this time. Cas takes a hit from that shapeshifter. I was angry but then...right after a stupid car accident. Something inside me broke and when I saw him sitting there one that bench, alone, wearing that ridiculous trench coat of his. All battered and bruised just like a hundred times before. All I knew at that moment was that I wanted to wrap my arms around him and hold him tight and never let him go again." At the last sentence, Sam watched as Dean's shoulders visibly relaxed. Up until the last statement, they had been hunched up nearly to his ears. The atmosphere in the room seemed to change for the better at Dean's self-revelation. Sam smiled his acceptance at Dean's words. Dean smiled his thousand-watt smile back at his brother and said; "I love the guy Sam, and I don't ever want to forget that or hide it from myself again."

Dean, tha...that's great!' Sam stood up and walked around the table to where his brother sat and grabbed him by the arm and hoisted him up, and wrapped his long arms around his brother into the biggest bear hug he could muster. "No matter what, Dean. You know I got your back, and Cas' as well" Dean pulled himself away and walked over to the cabinet and grabbed the peanut butter and bread down to make sandwiches. "Well, I know one thing for sure Sam. He is probably going to be hungry when he wakes, so I'm going to make him a PB&J. Grab a couple a beers and spend the afternoon binging Firefly and introducing Cas to the world of the Browncoats and Capt. Mal. Played by that dreamy Nathan Fillion." Sam chuckled and could only reply "Go for it."

Cas opened his eyes and looked around Dean's room. His brow furrowed, as he looked at the clock and could see it was now close to noon. Growing concerned at length of time Dean had been absent. The recovering angel decided to get out of bed and go in search of Dean. But first, he had to urinate.
Castiel exited the restroom and made his way gingerly down the hallway. He felt much better, and the wounds were healing quickly thanks to the small amount of grace he had left inside. Coming up on the entry that led to the kitchen, Castiel slowed at the sound of deep voices talking. He smiled knowing the two brothers were probably discussing the latest turn in events. He paused wondering if he should let them speak in private. Castiel knew that Sam and Dean shared a strong bond as brothers. Something he wished his own siblings would take note of and maybe emulate a bit more.

Deciding to let them talk Castiel began to turn away, and as he did so, he heard Dean's voice rise to a level that permitted him to pick up Dean's part of the conversation and as he listened. Cas felt the entire length of his body go numb. The words coming from Dean were cutting him deeper and doing more damage to his being than any angel blade ever could. Stricken. Castiel turned away quickly from the doorway and made his way back down the hallway towards his room. Dean's words playing through his mind like an awful demonic chant.

"So I feel like I need to go in there and tell Cas that everything was a mistake and that we shouldn't do this"
Dean wanted to tell Cas that it was a mistake. Dean wanted him to forget any of the last few days even happened.

"That we should just stay friends and that he should stay away from me."

Dean was regretting everything. Cas' fingers grasped clumsily at the doorknob that would open the door to his room. He struggled to get the rebellious fixture to turn. Finally, as the knob turned, Castiel pushed his way into his quarters and straight over to the chest of drawers. Pulling open the first drawer Castiel began to take some of the small momentoes that held special meaning and collected them on the bed. Making his way over to the closet that held his sparse wardrobe. Cas began to pull out his blue slacks and the white button-down shirt and laid them out. Castiel was going. He didn't know where and didn't care. He only knew that he had to get away from Dean before the hunter could come and tell him that they shouldn't be together. Unwrapping Dean's olive-colored robe from his body. Castiel began to get dressed and planned his escape from the bunker. Unseen.