"The thing is, it was my fault." The Doctor says quietly. "All my fault, really." Once he'd started telling Martha about home, told her the truth, he couldn't seem to stop. And she just sits, staring at him with that expression that didn't condemn or forgive. She listens. He isn't sure if that's better or worse.
"What was your fault?" she asks, leaning forward. "Not-"
"Everything!" he cries, throwing his arms out, "the War, all of it! It was me that brought it on, Martha. I did it."
"Doctor," Martha says in her soft, reassuring voice, "It was a war. It can't be all blamed on one person."
"You don't understand." The Doctor mutters, turning away. "I was the first sentient to land Skaro. Nobody had ever been on that bloody damned little red planet before. No offworlders. If it hadn't been for me, the Daleks never would have known there was more to the universe than their own little xenophobic war and their own speck of dirt. I proved to them that there was more to hate and fear than the other inhabitants of their own planet, because I was young and so damn curious. I was bloody stupid. Don't interfere, that was the law. The laws were there for a reason, and I broke them. Do you see what I did? I gave them their first boost!" He turns back to Martha, his eyes burning. "And that's not all. When I was given the chance to repair the damage I'd done, to destroy the Daleks before they became the enemy we fought, then, oh then all the rules were important. Oh my, I thought, I can't destroy a species. Not me, that's not my place." He stares at his hands, his head bowed. "And because of that choice, everyone died. Everyone…" he draws a shuddering breath, then looks up sharply. "And it wasn't just us either. They invaded thirty star systems before the high and mighty Time Lords felt it was their place to get involved. Billions died. Because of me, Martha. I killed my own kind. And so many others besides."
Martha stares at him, her eyes huge and sparkling with tears. Any minute now she'll order him to take her home, right now, and run out the door the minute she gets there.
She stands. Maybe she's going to take her chances here instead, run as far as she can get.
Then she wraps her arms tight around him. His breath comes in tight, unsteady gasps. She holds him for a long moment, before pulling away to look down into his eyes.
"I just want to say this, and I don't want you to say anything or answer me or anything. You mucked things up, and maybe you couldn't help your own people. There are planets that you couldn't save. But there are I don't know how many planets full of people alive today, and you did that too. You've saved more lives than I will if I work as a surgeon to the day I die. So…you told me a ways back that the universe has a pattern. Remember? I see three dimensions of the pattern and you see four? Well…if there's a pattern to the universe, and if everything works into the pattern, has its place and all, then maybe what was lost balances out with everything that you save. 'Cause you've done more than most whole countries-hell, than most planets manage to in the way of saving things. Maybe you were meant to do those things wrong, so you could do a lot of other things right." Putting out a hand, she wipes away the tears on his cheeks. The Doctor smiles weakly at her.
"Martha Jones. Oh, Martha Jones." He doesn't have any other words for her.
She hugs him again, then tugs at his shoulder.
"C'mon, Doctor. The TARDIS'll be waiting for us."