Unfortunately he was right. The Doctor had never asked her to kill. She had never killed, not in cold blood. The toclofane didn't count. They were... paradoxical. And confusing. And she hated it. EVerything having to do with it. Had he actually saved the future humans on one level, but at the same time he had destroyed them.
Martha placed down the bottle of water, listening to his words and found herself nodding slightly, walking off to find the gloves. She somehow managed to get them on befoer setting her eyes on the bag. She hadn't even realized it before she was punching it as hard as she could, gritting her teeth and just letting everything she could out. Her mind flashing back. Over and over again. And despite it all she didn't feel better. She just didn't. The more she hit the more it started bubbling up to the surface. The guilt, everything.