Edit: FOUND! - Brotherhood AU with hurt!dean and worried!caleb
I'm looking for a fanfic of the Brotherhood!AU I read many years ago. It was not written by Ridley herself or the other active brotherhood writers. It was very Dean-centric, I think he was around 16 or so? He and Caleb were fighting about something and Dean felt very misunderstood and lost the whole fic. He started doing dangerous stuff with some other hurting kid of a hunter. I remember something about him riding a motorcycle on a train track and in one of the last chapters they were about to enter an old unsafe cable car. In the end Caleb safed him and they made up. The fic had around 16 chapters or so and I think I read it on Fanfiction.net, but I can't find it anywhere. Thanks for helping!
Found it, it's called "Looking for space"
https://www.fanfiction.net/s/10796000/2/Looking-For-Space