There's a reason why Dean closes the door.

Tag to s09e12 "Sharp Teeth"

The first thing Dean noticed every morning after waking up was his closed bedroom door.

The first thought through his mind was a reminder of why it was closed.

He had once again screwed up and betrayed his brother's trust. And this time, this time, it had cost him big.

It had cost him his brother.

Without that closed door between them, as a physical representation of how he was now required to act, Dean knew he would quickly and easily slip back into the habits of a lifetime, habits that had started when he was just four and half years old.

There was a part of Dean, a very small part-a selfish part-that said he should be happy about the turn of events, that said he was free of the responsibility, that he should enjoy the freedom, that he had Sam's own blessing to ignore Sam's needs and put himself first for a change. He just didn't know how NOT to take care of Sam. It had been his job for as long as he could remember, and breaking a thirty year ritual was hard. So he kept his door closed to remind himself of all the things he wasn't supposed to do anymore…all the things Sam didn't want him to do anymore.

There might as well have been a list taped to the door for him to read, each time he left the room, which reminded him of the things he should and shouldn't do anymore.

Don't make ANY choices or decisions for Sam, no matter how small or insignificant they seem.

Don't bring him anything, unless he asks for it-even if you think he needs or wants it.

Don't tell him that it's time to do anything. (Eat, shop, laundry, take a break, clean his guns, sharpen his knifes, etc).

Don't tell him any jokes (NONE!).

Don't tease or insult him by calling him names like Samantha or Princess or Sweetheart.

Don't call Sam by any nicknames. (Not Sasquatch; not Gigantor; not Sammy; and especially not Little Brother).

Don't make fun of Sam's rabbit food or healthy eating habits.

Don't criticize any of his skills or offer suggestions for improvements.

Keep Sam informed of all progress and/or changes on their active cases.

Give Sam all the time and space he needs.

It was an hourly struggle for Dean to keep himself from doing all the things that he had always done for Sam.

In the week since they had returned from Wisconsin, it didn't seem to have gotten any easier to ignore his natural 'take care of Sammy' instincts. It probably never would.

Dean was doing his best, but it was hard and it hurt…a lot. He knew he would have to work hard to keep himself from crossing the line between partnership and brotherhood.

So Dean kept his door closed even though he didn't want to and no matter how much it killed him.

And it would stay closed until Sam knocked on it and asked (literally or figuratively) for Dean to open it again.

Author Note: Once again a million thanks go out to the wonderfully patient and amazing LoveThemWinchester without whose help this would not have been possible.