"I understand that, I do. You don't think that I'm missing someone too?" We don't have to ask who that person is now, do we? "But he can't fall apart on us now," Clint said to Star-Lord, before turning his attention back to Rocket, "you're a hero, act like it and fall apart later." It was probably a dick thing to say, but they needed Rockets A-game, not for him to fall apart like this.