We all know no one does the single man tear better than Dean.  This season, his best comes after being flung into the future five years and having the inevitable confrontation with Lucifer wearing his own custom made Sam suit.  Samifer's plan to wipe out humanity is progressing well and past Dean can only listen to Lucifer's "sympathy for The Devil" speech while seeing with huge heartbreak that Sam is really gone.  He won't buy the story, but this time in his defiance he lets his emotions slip.  He cries for humanity, for his brother, for everything lost.  So beautiful, so simply stated, yet emotionally powerful.  In order words, it's what Jensen does best.  We turn into heaping piles of mush. 
There is an honorable mention though, and it proves that Jared has taken notice in all those years of watching Jensen pull off the single man tear so brilliantly.  He gets a couple moments throughout the season to do the same thing, but none more powerful than the surprise visit from Jess, his dead girlfriend, in "Free To Be You and Me."  Jess comes with a message of guilt, that running away isn't going to fix things and it never has.  Her line "I was dead from the moment we said hello," was brutal enough but the kicker was the parting "Things are never going to change for you, never."  Sam may have had the single man tear, but I was sobbing.  Poor guy can't ever catch a break.