This is based on a prompt someone asked for on Tumblr. To all my Frozen readers, I'm sorry. It will be updated, but this just came to me. So I hope you all enjoy it!
It had taken him years to finally figure out when it was that he needed to go. Combing through the vast database of the TARDIS and his mind for one tiny little detail had been a bit daunting and time consuming, but he knew the end result would be worth it. As soon as he knew when he needed to be, he'd programmed the TARDIS and was quickly on his way. The rocky ride was so familiar now that he hardly noticed it anymore. She would've said something about it. She was always on his case about something. He'd be lying if he said he didn't miss her.
I was going to be with you… Forever.
He'd had no choice but to leave her behind. She would've died had she stayed with him. He wished she could've stayed. After she left, there was no one there to stop him when he needed it. Maybe the Mars accident would've happened like it was supposed to had she made him leave when he should have. But it was too late for that now. He'd had no choice but to leave her behind.
Rest of my life… Traveling… In the TARDIS…
The TARDIS finally came to a stop. He smiled at the screen, seeing that he was in the right place, at the right time. He grabbed his large coat, as it was snowing outside. He flung it around his shoulders and made his way to the door before stepping out into the cold air. December 27th, he thought. At least she had one last Christmas. It had been 20 years for her since he'd left her with her mother and grandfather. The obituary had said she had succumbed to the cancer that plagued her body. As he made his way down her familiar street, he knew he could only do one thing. He stopped right in front of the house she lived in.
He knocked quickly on the door. He'd seen that her mother and grandfather had outlived her, which he was sure had to have been dreadful for them. His suspicions were confirmed when Wilfred opened the door. The years and the stress of his granddaughter's illness had not been kind to him. His wrinkles seemed persistent at dragging his face down. His white hair seemed even brighter, if that were possible. But age couldn't hide one thing: the shock and happiness in his eyes when he saw who was standing in front of him.
"Doctor?" The elderly man asked, slipping on his glasses to make sure he was seeing right.
"Hello, Wilfred," he replied. "I'm here to see her."
His sad smile widened just a bit as he stepped aside to allow the Doctor to enter. The house hadn't changed much since he'd been there last. There were a few new pictures of the family that hadn't been there before, but the place looked virtually untouched by time.
"Her mother's up there with her," Wilfred said, pointing up as he led the Doctor to the staircase. "Doctors say she won't make it past next week," he added sadly.
"Wilfred, she won't make it past tonight. That's why I'm here."
You're not special. You're not powerful…You're not clever. You're not important.
When he'd been going through her information, he'd seen what her life had been like after he'd left her behind. She'd had another failed wedding, this time the groom's ex swooping in the day before. Temp job after temp job after temp job was all she had. He'd even managed to find an audio file of one of the therapy sessions she'd had to go to. "I just feel like something's missing," she'd said. "Like it's there, but I can't reach it." That made his hearts hurt. And he was going to change that.
I'm so sorry… But we had the best of times.
Wilfred only nodded before leading the Doctor up the stairs. Of course, he remembered exactly where her room was. It was where he'd left her. It was where he was going to leave her at the end of the night. He knew once he'd set his mind on what he was going to do and saw her date of death that he was the reason. But she needed to remember. After the life she'd lived, she needed to remember.
Wilfred knocked on the first door at the top of the stairs and opened it slightly. The two men could hear a quiet conversation between the two women inside the room. The Doctor saw Wilfred motion for someone and say, "There's someone here." A moment later, Donna's mother appeared at the door. Her face showed the same shock that Wilfred had, but not any of the joy. She stepped out into the hallway and shut the door behind her.
"What are you doing here?"
"I'm here to help her," he said, sadly and simply.
She rolled her eyes. "Oh I was unaware that Time Lords could cure cancer."
He sighed heavily. "I can't do anything about that… But Donna needs…no…deserves to know the kind of life she had. The difference she made."
"You told us if she ever remembered that she would die…" Sylvia trailed off as she realized what he was saying. "No. You're not doing that to her."
"I am so sorry. She's going to die tonight, Sylvia. I've seen it." The Doctor turned his attention to the door that had his best friend behind it. "December 27, 2028, Donna Noble draws her last breath." He turned his attention back to her mother. "Let her remember how amazing she was."
Sylvia seemed to contemplate this for a long time. No parent was supposed to bury their child, but she knew that it would come down to that. She'd known since the doctors had said there was nothing they could do anymore. She wasn't responding to treatments, and the cancer was spreading. Tears sprang from her eyes and ran down her cheeks. She sent one last glance at the door. "Make it quick, will you? She's miserable," she said, her voice breaking. Wilfred took her in his arms as she started to cry and led her downstairs, leaving the Doctor alone in front of Donna's room.
He took a deep breath before pushing the door open slowly. Donna was lying on the bed with her hair splayed out on the pillow. She had an IV going into her skinny hand. She looked frail. The Doctor hadn't expected her to look so broken and frail. This wasn't Donna Noble. This was the shell that was about to be left behind. He was determined to fill that shell before it was too late. She looked over at him with weak eyes, the lamp by the bed the only thing lighting up the room.
"Hello?" She said, a bit questioningly. "Who are you?"
Of course she wouldn't recognize him. It had been twenty years and for her, they'd only met for the briefest of moments. The Doctor felt tears well up in his eyes, but he had to hold it together. He had to hold it together until she remembered.
"I'm the Doctor," he said, just as he had all those years ago. "You?"
"Donna," she replied, like he was already supposed to know.
"Yeah! Is that optional?"
He smiled a bit. Even on her deathbed, Donna was still as sassy as ever. "Well, it is for me." She winced a bit and looked around, a bit confused. "You alright?
"Yeah… Just a bit of déjà vu is all." She looked up at him, puzzled. "Have we…met before?"
The Doctor sat down in the chair next to her bed. "Donna… What if…" He stopped for a minute. He hadn't really thought out what he was actually going to say to her. "Donna… Imagine another world, another place far from here. Not anywhere on Earth."
"What are you going on about? Not anywhere on Earth?"
"It will just be…easier if I show you."
She looked confused as he started to put his hands on either side of her face. Had she had the strength, she would've pushed him away from her, but her body wasn't up for that. As soon as his hands made contact, he began to break down the walls he'd created all those years ago. No longer suppressed images flashed before her eyes. Memories once lost flooded her brain. The Racnoss, the Adipose, Pompeii, the Ood singing of Donna, the Sontarans, Jenny, Agatha Christie, the Vashta Nerada, Midnight, dying so the Doctor could live, the Earth flying across the universe and defeating Davros and the Daleks. It all came flooding back.
And for one moment... one shining moment... she was the most important woman in the whole wide universe.
"Doctor…" she said. Donna couldn't believe it. He'd come back. He'd given her life back.
"Oh, Donna… I'm so sorry…"
She shook her head, taking his hand. A tear slid down her face. "How long do I have?"
"There's no way to tell. You won't last through the night, though…"
Donna nodded. She'd accepted that the cancer would take her life long ago. She'd much rather die this way. "Will you stay?"
The Doctor gave her a sad smile. "I'll be right here, Donna."
The two sat in silence as Donna closed her eyes and relished in the memories that had been gone for so long. As the night passed, he slowly felt her grip on his hand loosen more and more until finally, it was totally slack. He pressed his fingers to her neck and sighed.
December 27, 2028, Donna Noble, the most important woman in the whole wide universe, drew her last breath, with her best friend by her side.