I just needed to write this because I feel like it must've been hard for Rose to not get to say goodbye to Nine before he regenerated, and how at some moments she must wish for him back. Hope you enjoy!

"What was that back there?" Rose was standing by one of the railings in the console room, watching the Doctor fly the TARDIS away from their last adventure and into the vortex for some maintenance. The rocking motion of the sentient ship stilled, and Rose continued to stare silently at the Doctor until the pressure to answer became too much for him.

"What was what?"

"He said it. He said that he assumed we were together and you made a face." It had just been a man, a man they had met whilst saving the world they had been on from an alien attack. No-one particularly different than anyone else who had ever assumed the exact same thing about them.

"So?" The Doctor pushed a few more buttons , not meeting her gaze. There was definitely something wrong, then. Before, she might've thought she was imagining things, but his inability to look her in the face and grin at her like he always did confirmed her suspicions.

"Well people assume that all the time. It seems obvious to them." In Rose's head she was itching to tell him that it was obvious to everyone but him, but she exercised self control. "And you never normally get like this."

"Well maybe I'm just sick of it, that's all." Rose felt herself shrink back slightly. That hurt. Why would he mind? He had never minded before, he had even enjoyed people making assumptions about them, she was certain.

"What are you talking about? Sick of it, what does that mean?" Maybe it would've been wiser to leave it alone, but she was standing there in the TARDIS with him, and he was doing that thing where he pretended to look at the console so he could avoid eye contact with her, and Rose just couldn't stand it any longer.

"It was nothing, Rose, something and nothing, it doesn't matter now." He shifted, looking at the screen and not at her. Rose couldn't stand it any longer.

"Why can't you just tell me? Why are you always trying to avoid giving me a straight answer? God, this was so much easier before you—" She cut herself off, unable to finish that thought, never mind that sentence, because she could tell just by the Doctor's face that he knew what she had been about to say.

"And there was me thinking that you understood that I was still the same person, that I still am the same person, always!"

"I do understand that, I really do, you know I do! But it's just... I got back to him, to you, when you sent me away on the Gamestation. When I woke up, the last thing I could remember was the wanting to get back to you so badly that I would do anything, the feeling that you were the most important thing that I had to save – not the universe, just you. All of a sudden I'm back and you're here and the Daleks are gone, and then you turn into another person right in front of me. Now I get that you're the same person and everything, but can't you understand why I might miss the last you, taking into account the lack of closure or even a proper goodbye?"

The Doctor had his hands in his pockets now. Rose felt uncertain. They had never done this before – sure, they had argued, but this was something very different and she wasn't sure she liked where it was headed. "So, you blame me for regenerating without saying goodbye." He didn't sound angry or understanding or even confused. His words were even; his tone perfectly balanced in order to stop Rose knowing what was going on inside his head. Not that she had to wonder for long.

"No, of course not, but I just wish it could've been slower, it all happened so fa—"

"Do you want to know, Rose? Do you want to know what happened that day? Because I'll tell you the truth if you want to know!" He stopped, waiting, looking at her face for a reaction. Rose did not waver, her eyes boring into the Doctor's as he began to unleash some of the anger that she had never thought would be directed at her. "I saved your life. You absorbed the Time Vortex to get back to me, you destroyed the Daleks and you brought back Jack, but you were dying. The Human mind isn't built to deal with that kind of power, so I took it from you. I managed to give it back to the TARDIS, but the effort and the damage it caused nearly killed me. That's why I regenerated. That's why I became this. Because of you. I gave my life for you, Rose! I gave up everything that I was to save you, and yet you still can't be satisfied with just me – you want him back!" The Doctor broke off, fury blazing in his eyes, his body rigid. He seemed torn between staying to see what her reaction was or simply running away, the way he always did.

Rose was utterly stunned. She had always wondered what had happened on the Game Station, but her joy at finding her way back to the Doctor again and her shock at his regeneration had driven any thoughts of an explanation out of her head.

"I'm sorry Doctor. I didn't know. You could've told me all this before – it was something I needed to know."

"But you do want him back. Don't you?" Rose didn't answer. "Don't you?!"

"Fine! Sometimes I wish you were still the old you. Are you happy now, is that what you wanted me to say?"

"Of course, Rose." His voice had picked up a deeply sarcastic tone that didn't suit him, and Rose found herself attempting not to wince, as if his words could actually leap through the space between them and strike her – she had never heard him sound so angry since...well, ironically, since he had been his previous self. "That's what everyone wants to hear, that their best friend wishes they were someone else. They changed to save their best friend's life and now she doesn't want them any more."

Rose threw up her hands in frustration, turning away and pacing across the grating in an attempt to get a grip on this conversation that was spiralling out of control, hurtling dangerously fast towards being a full blown fight. His over use of the term "best friend" didn't help either, considering what it was that had sparked off the entire argument.

"It's not that I don't love this you." She realised that she had said 'love', but ploughed on regardless, trying to sort out how best to explain herself without hurting him more. "In fact I really do, but the other you...well sometimes he was just easier to read. No, really!" The Doctor had let out a humourless laugh, clearly not believing her. "I know it sounds backwards, but it was just easier to know what was going on in your head back then. Now you're so...so different. You give me mixed signals, you're not jealous any more really but you flirt with just about everyone and I just don't know where we are any more!"

She stopped, taking a deep breath. "We can't go on like this forever you know. At some point something's going to happen."

"And how do you know that?" Rose relaxed a little – the poison was gone from his voice now, she wasn't afraid of his words any more though they still caused her pain. She could see that his shoulders had slumped, like all the fight had suddenly gone out of him, a puppet with no strings.

Rose stopped herself from shrugging, because the answer to how she knew was simple. "Because I know how you feel. And that's the problem! That's exactly it – something's going to happen, but if you're going to be like this then it might not happen the way that it should and then things'll go wrong and..." She was aware that she was beginning not to make any sense, even to herself, but she had to try and make him see the logic that had driven her to this point. "I'm going to bed." She had not expected herself to say that.

She could see by the Doctor's face that he was hurt and confused and wanted to say more – which was an accomplishment on Rose's part, the fact that she had managed to get him to actually want to talk about his feelings – but she wasn't in the mood now. She had said too much, she had hurt both of them and she needed to sleep on it before she decided what on earth she was going to do next. If anything.

Rose walked towards the door, pausing for a moment without quite knowing why. It felt like there was something else she needed to say. Ah, of course. It was only polite.

"About the regenerating thing." She felt him freeze from the other side of the room. "Thank you for saving my life," she said over her shoulder, not daring to look at him again before she disappeared down the corridor.

She barely heard his answer; in fact she was almost certain that the TARDIS had amplified it just so she would not miss the words he whispered after her. "Thank you for saving mine."

I hope you liked it. There should be one more chapter coming, this was only ever destined to be a short fic. Anyway, review if you want, and my tumblr is .com, in case you want to know :P