Note: This may continue if I have the free time to write it. I'd like to keep going with what may have happened in the series. Apologies if there are horrific, glaring errors in this, but I just had to get this plot-bunny out of my head.
Disclaimer: I don't own Doctor Who.
When Donna awoke, it was to find the Doctor perched in a chair by her bed, elbows on knees, fingers steepled, all awkward angles and nervous twitching. It took Donna a moment to gather herself.
"What are you doing in my room?"
The Doctor stopped twitching, appearing to come out of a trance. "You-"
"What, is this some kind of perverted alien thing?" Donna clutched her blankets around herself, sitting up in the bed. "Do you do this to everyone who travels with ya, or just with me? I've told you before, I'm not interested-"
"No, no, no, no, no, Donna, sorry, just-" The Doctor shot up out of his chair, backing away across the room. "Just checking, just wondering, you know, how you are, if you're feeling all right-"
"Oh, no," said Donna, instantly apologetic. "Is this some kind of-I should have realized, what happened on Midnight, do you need someone close by or something? I mean, I'm not much good at being comforting, really. I could make you some tea," she offered. "Lemme just find my robe and slippers, I'll be right out."
"Midnight," said the Doctor, still backing away. "Right. Had a bit of a...nightmare, sorry, won't happen again." His back hit the wall, and he glanced to his left to find the door. "Yes. Um. You are feeling okay, though? No...headaches or anything?"
"You're dafter than usual this morning," said Donna, putting on her slippers as she tied her robe. "Right. Tea." She moved to exit, but the Doctor was standing in the way. She gave him a look.
"Tea," said the Doctor, staring at her blankly. A wide grin suddenly split his face. "Right! Tea! You are brilliant, Donna Noble! Really wonderful!"
"Don't forget it, spaceman," she grumbled, poking him in the chest to clear the doorway. "Anyway, you've never had my tea before, and I guarantee you, once you have, you'll never wake me up after a nightmare again."
Earlier
One minute she was talking about visiting Felspoon, the next her brain was sort of fizzling around the edges and she knew, oh, the horrible truth of it, and the Doctor took her shoulders. "Donna...oh, Donna Noble, I am so sorry. But we had the best of times. The best...goodbye..."
"No," she blurted, beginning to get frantic. He was going to take it all away, send her back to Chiswick and temp work and celebrity magazines, and the dull, awful not-knowingness of ordinary life. "No, no, please! NO. Give me a minute," she backed away from him. "Just a minute," she begged. "One minute."
"Donna, I know it hurts," he said, and he knew because it was hurting him, too, seeing her in pain. "Let me help."
"Look, your idea of help is not very helpful right now!" Donna took a few deep breaths, hand on her forehead. "Now shut up a minute and let me think. It's not like I've had much of a chance up until I got your blooming big brain, have I?" They exchanged weak smiles across the room.
"A minute," said the Doctor.
"Shush!" Donna turned away and fought against the burning in her brain. For a short amount of time there was only the sound of the TARDIS humming. Across the room, the Doctor made a move to advance, to reach out to Donna, but as he stepped forward, she turned to him. "You enormous outer-space idiot."
The Doctor stopped, affronted. "What?"
"What, you're just going to use telepathy to take away all my memories? Oh, that's the only solution, obviously, always has to a martyr, doesn't there, so you can mourn the loss of another companion," she crossed the room to him, and mimicked crying with her hands. "Oh, boo hoo, I'm the Doctor, I'm always alone, and this is the only way."
"There are no other-" Donna's knees buckled as she clutched her head in pain. He caught her by the elbow. "Please, Donna, can I just-?"
"Chameleon arch," Donna gasped.
The Doctor stopped. "Chameleon arch."
"You know, for someone who's usually so reliant on technology, you get the funniest ideas in your head in a crisis. Oh, it can only be solved by taking away all of her memories since she first met me," she grated at him.
"It's the same thing, Donna, the chameleon arch, we'd still have to-to input new memories, it's designed to give you a new persona-"
"What's in here, rocks?" Donna knocked on the side of his head. "My brain's burning from the inside and I still think better than you! Put my memories in there, except for the ones with the metacrisis, I'll never know I had any kind of Time Lord anything, and-"
"And if it can make me human, it can do the same to you! Donna, you're amazing!"
"And you're a...bonehead," she said, sinking against the console chair.
"No, it won't work!" The Doctor turned away, tangling his hands in his hair. "That'll take ages to set up, and you don't have ages-"
"Knock me out, then! If I can't think, I can't hurt myself, right?"
"Right?" asked the Doctor of himself. "Right? Right. Right! Right!" He dashed to the infirmary, reappearing seconds later with a tranquilizer. "See you soon, Donna," he said, giving her the injection.
"Donna, wake up. I'm so sorry, but you've got to be awake for this part, or it won't work. But it's going to hurt, very much, and I'm sorry."
Donna blinked, becoming aware of the Doctor's face in front of hers, then the TARDIS walls behind him and then the explosive terrible pain in her head. She scrunched her eyes shut again. "OW."
"I've talked to your mother, and your grandfather." He was making last-minute adjustments to the machine, and lowering the headset over her hair. "They'll know not to mention any of the-anything about the stars disappearing, or any of it."
"Good." She forced her eyes open again.
"Donna." He stood still in front of her. "What happens if you ask me about it? What if you want to know?"
She met his eyes. "Just tell me I forgot."
The Doctor nodded once, and turned on the machine.
Later
"You're right, this tea is truly awful," the Doctor said, sipping it and making a face.
"Oi!" protested Donna. "And you're welcome for comforting you after a bad dream!"
"No, it's astonishing, really, I know you warned me, I just hadn't known that anyone could really ruin tea, I mean, there's the Limpkoshians, right, they make tea out of the poisonous Sakkar bush, but to just take an ordinary teabag and turn it into something undrinkable takes a really rare talent."
"Shut up!" He grinned at her to show her he didn't mean it, and the two of them fell silent, sipping their tea, and the Doctor eating a biscuit, because after what he'd just gone through, he really, really deserved a biscuit. With chocolate in it. Possibly two biscuits.
"Oh, you left this in the control room," said the Doctor, extending a fob watch across the table to her. Donna wrinkled her brow and took the watch.
"Oh, dunno how I let that get away from me..."
"Might wanna put that somewhere safe."
"Yeah," she tucked it in her pocket, and promptly forgot about it.
"Donna," he caught her attention again. "Safe."
"Safe! Got it! Thanks!" She sipped at her tea again, rolling her eyes.
There hadn't been any ill effects that he'd noticed, so far. He really wouldn't know if the process had worked until three or four more hours had gone by. But he thought it'd worked. He wanted so badly for it to have worked that it could almost make it true. 'Cause there was Donna Noble, sitting across from him, right as rain, and still knowing who he was. He grinned at her.
"What?" she demanded. "Have I got somethin' on my face?"
"No," he said happily.
"Then what's with the staring?"
"Just glad to have you here."
"Right," she said, still suspicious. "You got any books on Time Lord psychology? I reckon you've got some kind of mental disorder."
The Doctor grinned and helped himself to a second biscuit.