"That's what friends are for," Tony responded, not at all petulant. "Arguing and wanting to punch someone you're close to is perfectly normal." Actually punching them -- well, maybe not so much. That was part of the problem, really.
"I never thought you were incapable of it. Everyone lies. I'm well aware." He stood up a little straighter, glanced away for a moment and found he couldn't even keep on talking in circles about it. If Steve couldn't figure out why one written letter apology about not telling Tony about his murdered parents and a i'd probably do it again if I had to wasn't doing it for Tony, there was no real point in trying to further explain. Tony was simply too tired for this, anymore.
He looked back over at Steve at the sound of his name, chewed at the inside of his lip as he listened. "I don't want anything more," he said, honestly, slowly. "I never wanted anything in the first place." It felt very much like this was the wrong answer. That they weren't really resolving anything. But Tony didn't know how to fix what was broken here - and it was sort of infuriated since he was supposed to be able to fix anything.