For a few months, he pretended that she was still on board. Those fleeting moments before the second visit to Bad Wolf Bay had fed him for a while, a very short while. He would close his eyes and listen to the silence that surrounded him. Eventually he would hear Donna's voice, telling Jack that she thought that he might be the best at piloting the TARDIS. He could the absolute joy shining on Martha's face, her eyes totally bright with happiness. And Mickey, not so thick; he had found his place in the world. In any of the worlds that he might finally choose. Sarah-Jane, she was there when Davros began it all and now she had witnessed the end. Then there was Jackie Tyler, thought that all problems could be solved with a nice cup of tea. Turned out that she was mostly right. Then there was her...
... Rose Tyler. The woman that he thought he could never see again. The woman who had done so much just to get back to him, he amended that thought then... not just to him, but to save the worlds... again. He hadn't thought that possible, but she had managed it. Typical Tyler, not going to be stopped. What the Doctor hadn't accounted for... what he really should've thought about, was his hand. His handy spare hand. Jack, trust him to find any old spare body part and keep it in a jar. He never did find out exactly how Jack managed to come by it.
The meta-crisis had been obvious really, the only way that this particluar story could've played out. So here he was, alone again. he kept his eyes closed. Rewinding to the moment when he hadn't re-generated, to the moment when he had been able to hold Rose so very, very close to him. he wished that he had never let go. But he had. So, just for a few moments, he would pretend that she was still on board... with him.