It's the hitch in her voice that breaks him. "I'll just," he says, gesturing toward the sofa, and she nods, bringing her hand to her lips. Not a kiss; a shield. He continues to not look at her as she turns and walks down the hall. The door to her bedroom clicks shut, louder than a gunshot. The silence in the flat is stifling.

He sits, gingerly. Comfortable sofa. Tasteful shade of beige. A bit bouncy. He sees hints of her, strewn about, clues to the life she's led without him. Pictures of herself, her mum, a little boy with big eyes, Pete. A photo of her and Mickey, mugging, a zeppelin in the air behind them. He thinks of what she said, about kissing Mickey and thinking of him, and feels heat flash through his chest. Jealousy that she was kissing Mickey? Excitement that she was thinking about him? Despair, because she'd said him and not you?

His thoughts are a frantic, wordless jumble in his too-small brain, uncontrolled hormones and unfamiliar impulses making him feel as though he's stuck inside a wind tunnel. He's surprised by how knackered he is. Exhaustion feels like a pillow over his face. Is this what he has to look forward to? Forty, fifty years of decreasing energy and soul-numbing heartbreak? His hands itch to tinker with something, rewire the heating circuitry, check her electrical system for optimal output. He can hear Rose undressing in the next room and the synapses fire again, the urge to go after her so strong he has to grip the arm of the sofa to hold himself back.

Kicking off his shoes almost angrily, shrugging out of the jacket that feels two sizes too small. Doesn't know where to put things - a pile on the floor? Folded on the coffee table? The simple act of sleeping is fraught with so many unexpected pitfalls. For example: the loo. Should he use it now, or later? There's only one, probably, and he doesn't want to presume. Also, he has no toothbrush. Some of his incarnations had dodgy teeth, but he's rather vain about this set. His only set, now. He's no longer someone who can forget to floss.

And in the morning - he doesn't want to think about the morning. Doesn't want to think about any of it, really. Not today, with his disappearing TARDIS, the joyful smiles of the people he'll never see again, the look of blossoming grief on Rose's face as they stared at each other on the beach. Not tomorrow, when they will have another awkward not-conversation and he will have to decide whether it would hurt worse to leave now or later. If he can compartmentalize - and he's always been very good at compartmentalizing - he might be able to keep it from driving him mad.

From behind a closed door, he hears Rose opening and shutting her bureau, sliding between the bedclothes, sighing.

He tells himself he had no expectations. There was no time, although the minute the other him said the words DÃ¥rlig Ulv Stranden he knew what was to come. It had been a shock, to be sure. Up to that point he'd assumed Rose was where she belonged - with the Doctor in the TARDIS - and he'd have to love her knowing he'd never have her. Not like he, the eternal he, wasn't used to that. But then the beach, with the ocean crashing and the sound of the screaming Daleks still echoing in his head, Donna and the Doctor finishing each other's sentences and Rose kissing him, him, while the universe sealed them in like a prison. His holier-than-thou counterpart believing he'd given them both a gift. Believing they were his, to give.

He was right about the lack of words. He doesn't have the language to express the way this is destroying him. Has always destroyed him, although now there's the added bonus of having given up his life, his home - not his, but his in all the ways that matter - all for love of Rose Tyler. The sort of grand romantic gesture he'd always mocked and secretly coveted.

And all she wants is the part of him that could never give that to her.

He tells himself he had no expectations but that's a lie. He can see with eyes that aren't his eyes her brilliant smile as she ran toward him, feel his hearts (only one now, such a strange thing, like he's broken) hammering in his chest as his feet skimmed across the street, thinking only of reaching her.

Somewhere, the other Doctor is standing in the rain. He doesn't know how he knows that.

I would. I would let the water soak me to the skin, partly because I've just given up everything that matters to me and my body is numb and distant, partly because I'm a melodramatic bastard. And then I'll go back to the TARDIS, to the last home I'll ever have, and I'll tell myself I did what I had to do.

He buries his face in a cushion - Rose hasn't thought to bring him a pillow or a blanket, not that she should - and weeps for Donna, for what the man who is also him has done to her, and also for himself. For knowing.

He doesn't know who Rose weeps for.