"But it's still not right. Because... the Doctor's still you. Both of you."

He should have left them both on that beach, as he'd planned. They could have lived long and brilliant lives together, safe, away from him. He would never have had to see or even imagine this moment. In his mind, she would have always been young, vibrant and so alive. Even though he would have been miserable without her, her happiness should have been enough for him.

It hadn't been. Not when she'd dangled the promise of more before him.

"All right, answer me this. Why can't we stay in the TARDIS? Both of us. With you. You and I can make him better together, yeah?"

It was a terrible idea to let the other him stay. Not because that second man was dangerous, or because the he'd have to watch himself grow old and die. It wasn't even that they'd have to share Rose.

No, it was because it was hard enough just meeting his own eyes in the mirror. At least when it was his own face, the Doctor could school his expression into neutrality. He was incredibly good at hiding his true feelings in this incarnation, after all. When his eyes accidently caught their own reflections, he could almost ignore the fact that he was seeing into the soul of a killer of millions.

However, it was impossible to pretend that way when the other version of himself looked at him with obvious blame shading his scrutiny, as he was doing at that moment. There was no way for him to control that.

They both knew what he'd done. He'd never be able to forget it, especially with the part-human man around to serve as a constant reminder.

Good. It would be better if he never forgave himself. It was too important to have any lesser impact than completely shattering him. Both of him.

"There's no reason why we can't, is there? Not really. You're just bein' stubborn again. I want to stay with you, Doctor. Both of you. I promised you forever, remember?"

He'd always known that her forever couldn't last, but he'd hoped... maybe it would last almost long enough. He'd prayed to a deity he didn't believe existed that she would grow old and he'd be able to hold her hand as she quietly slipped beyond consciousness and the trappings of life. It would have been painful for him to live through, but it meant he could have had all of those years in between with her.

He was always going to have to lose her, one way or another. In the end, he'd agreed to bring them along because he'd thought that extra time with her would be worth the pain of watching her wither with age and sickness.

He'd somehow forgotten that he could be robbed of even that.

"Oi," Rose admonished as the two Doctors faced off in the doorway of the TARDIS. "Now, don't fight."

It was an odd moment, hearing his words of years past echoed back at him. He realised how his companions must have felt, suddenly learning they'd have to get along with some other person who was important to him.

He wasn't the only one she loved anymore.

She reached for him, her fingers entwining with his, while her other hand still grasped the part-human Doctor's. With the broad grin and the excited energy he'd missed so much since losing her, she tugged them both inside the TARDIS.

The Doctor thought he could live with being one of two as long as it meant he was still hers.

"I'm sorry," the Doctor said finally. He squirmed under his duplicate's furious glare. "I'm so sorry."

"You were right there," the other Doctor accused. "You could have killed them before they could hurt her. You could have saved her!"

He couldn't have, though. Even if he'd seen it coming, he couldn't have just killed them all without giving them a choice. Even for Rose, he couldn't have done that.

It destroyed him slowly inside knowing that this other man, with just enough humanity in him that he could put the woman he loved above everything, could have done it. If only he hadn't been so far away. If only Rose had been standing beside him instead.

She might have been alive, then.

The other Doctor's eyes closed and the anger that had sketched harsh lines into his face fell away to clear the path for grief. He leaned over Rose's prone form and his shoulders shook as tears flowed down his face, eventually dripping messily off his jaw line onto Rose's jacket.

That other Doctor had enough humanity, and enough of Donna especially, in him to cry freely for Rose. The fully Time Lord Doctor didn't. He couldn't allow himself to cry. He didn't deserve that catharsis.

"I want to go everywhere. We've got all of time and space. I want to see it all. I don't care where we go first. You two can choose."

He couldn't help but think that he'd made this hell in which he had suddenly found himself. He'd tried to have the best of all worlds, with Rose Tyler at his side, and another version of himself along to help keep her safe, and the universe at their fingertips.

Instead, he'd lost everything.

Those eyes – perfect copies of his own – burned into his skin again as the other Doctor looked up from Rose's body.

The Doctor couldn't stand the condemnation. He'd never been a man that dealt well with consequences.

He walked away, leaving them together just as he should have done in the first place. It was too late for that to do any good, but he couldn't stay with them any longer. He'd completely lose his mind with the grief and guilt.

He wasn't just leaving her there, he assured himself. The other him would look after her.

"Coward," the other Doctor called bitterly after him.

Every time.

~FIN~