I'm searching for a story that starts at the end of season 4. Castiel tries to save Sam and Dean from Lucifer, but can only take Dean because Lucifer is holding on to Sam or something. Then Castiel takes Dean to an alternate universe where Dean's parents are alive but Other!Dean is a jerk who does drugs and mistreats his family. Other!Dean goes missing and Normal!Dean shows up on his alternate family's doorstep. That's all I remember. If you can help me I'd really appreciate it! Thank you in advance!

ETA: Found! There's a Hole in the Fabric of My Reality by extrix