Tony thought what he was doing was right. He had to - he had to believe in himself first because no one else would... not now. When a young SHIELD agent had gotten Pepper caught in the crossfire of an attack, he was lost. He couldn't even tie his shoes without her and now she was gone.
He wouldn't listen to reason from anyone from then on - fighting against SHIELD at every turn and nearly drinking himself to death in the process. He turned against his teammates - against anyone standing in his way. He was going to bring down SHIELD no matter what the cost. Recklessness had cost him Pepper and he was finished fighting for the sake of good. What had it ever gotten him but heartache?
He was merciless but sloppy in his vengeance. He didn't care who else he had to hurt. It wouldn't bring back Pepper, but he had to make them pay - to make them suffer like he was every moment without her.
