From Chapter 19:
"He slammed the emergency button of the elevator, effectively stopping it in its tracks, then sat down and twisted the metal quiver open. White smoke blew out of it just like he remembered. He took out an arrowhead filled with a green liquid—was this supposed to be ironic or something?—and flexed his left arm, making the veins stand out and throb. They looked darker than their usual pale blue.
His hand trembled in the air.
Was he really doing this? Hiding away to stick needles in his own arm like a goddamn junkie. What if this stuff made things even worse? He had no idea what he was doing. But he had to try it. He had to do it on his own. There was no other way.
He couldn’t tell Bruce, he fucking couldn’t.
When you start caring about people, you push them away. You let them down. That’s your superpower.
He winced.
Next time, you’ll shove your doubts up your ass and you’ll fucking speak up or I swear I’ll break both your goddamn legs.
He ran a hand over his face, then let the arrowhead fall down on the floor and curled up on himself, for a long time.
“Hey, Jarvis,” he mumbled at last.
“Agent Barton, sir?”
“Can you… could you… call someone for me?”