Sam had tried to do things on his own, tried to be strong. Dean had given his life for him, sold his soul to bring him back and he still kept screwing things up. For months he'd tried and the blood gave him direction, gave him purpose. It was the focus he needed to channel his power and do something worthwhile.

And it had all gone wrong.

"Can't.. can't get.. warm," he stammered out, curling himself around Dean in a desperate attempt to try and warm himself.