Dean was sitting in his hotel room on the edge of his bed. Sam was watching him from the table in the centre of the room. Dean had been back for a long time and Sam often caught him in one of these states. He just sat there staring into space, Sam didn't know what he was thinking about and he didn't ask.
Dean took no notice of Sam staring at him, all he could think about was what he had done and how he should have stayed and tried harder. Dean should have held on tighter and not let him let go. All he could think about was that moment and that he was never getting him back, but Dean didn't think he could go on without him, Dean had never told him the truth and he will always regret that.
Sam saw a tear roll down Dean's cheek and he thought that he should give Dean sometime to himself so he got up and went to the café down the street where he could keep doing research. Dean was left alone in the room and upon realizing this he curled into a ball and started sobbing into his knees. He heard a faint flutter in the room so he looked up but saw nothing.
He was lying on his bed silently sobbing and muttering what he always should have said. "Cas, I don't know if you can hear me but I love you and I always have and I need you to know that so that while you are stuck you can have some hope. You better not be dead Cas, you keep fighting until you get out." Dean started sobbing again and he felt someone lift his chin up "I did keep fighting Dean, and I always new you loved me, I love you too."
Dean's eyes flew open when he felt someone else's lip press against his. "Cas!" Dean muttered against his moving lips. Cas broke apart and looked at him, Dean threw himself at Cas and pulled him into a bone-crushing hug, Cas tenderly hugged Dean back and Dean finally had what he wanted, his one and only Angel.
Sam walked into the hotel room and looked at the bed, he saw Dean and Cas lying with each other, Dean peacefully asleep in Cas's arms and Cas had his eyes closed and looked content. Sam backed out of the room silently and closed the door. He turned around to see Lucifer staring right at him, almost into his soul. "Don't worry Sam, you still have me." He weakly smiled at the hunter and the hunter returned this smile. Sam's arms wrapped around Lucifer's waist, "Yeah I will."