Headcanon: Phil Coulson lives, yes, but at this very point he knows for certain he must fake his own death. For the Avengers to work, Phil must die. Phil has to leave his life behind. He has to commit to this lie. He has to leave everyone, everything. He has to go into hiding. See the tracks of a tear down the side of his face? Phil sheds that tear for Clint. Clint who he leaves without saying goodbye too. Clint who will believe the only man he’s ever loved has been killed. Clint who he loves in return. Clint who had had plans to marry. Clint who he will never see again.