Ne Me Quitte Pas
He doesn't realize how much he loves her until she's laying in front of him, bleeding, by a bullet that was meant to take his life, not hers. His mind races back to the talk they had after he learned the truth. Back to how cruel he was with her, all the accusations and bitter words.
He felt betrayed, cheated by the one person he trusted more than anyone else. He wanted to hurt her, like she hurt him so he pushed her away. Told her she was nothing more than an ally and that was the biggest lie he ever said.
He treated her like a complete stranger and not like she is the love of his life. Because he loves her, he honestly, truly, loves her and he needs her. More than he needs air to breathe and, boy, how did he regret his behavior.
His gaze rests on her pale face as he watches the doctors work on her from the observation balcony and he prays to whoever God looks over them to let her live, let her survive this too and he'll make everything all right. He'll apologize as soon as she wakes up and tell her how he feels.
Because he can be Coulson without May but he can't be Phil without Melinda. She's a part of him and he simply can't live without her.