"When the fighting first broke out, I thought to myself, all right, O'Brien, you've done this before. Keep your head down, focus on the job, you'll get through this just like you did in the last war. But this war's different. Maybe I'm different. I have this growing sense of isolation. I see people, I talk to them, I laugh with them. But part of me is always saying they may not be here tomorrow. Don't get too close."