Maybe its not over- Donna is starting to remember the Doctor and her grandad contacts the Doctor worried , The Doctor then rushes over but finds Donna is perfectly fine which is mystery to him and he keeps asking if shes is ok. But when he sees that she is ok, he sees a chance to have her as company again.
The Doctor was sighing, he was leaned back in his chair by the console, he was still miserable and lonely without Donna, though he had met many interesting people he was thinking it wasn't safe to travel with anybody else.
And Rose was with his meta-crisis duplicate. And everybody else had their own lives and didn't need him, he had thought he would be ok alone, but he wasn't . But he knew it was risky for Donna to even remember him, so he stayed far away.
Closing his eyes , The Doctor decided to take a nap in his seat. He was exhausted from saving the day, he didn't have assistance that time, he knew that he could have asked any of the people he had met recently, he knew it would just end in heartbreak again. Sleeping where he was he was dreaming of his past adventures with his friends.
He had an arm across his face.
He seemed to sleep longer than he wanted to and sat up in his seat and leaned over the console and started flicking buttons.
He hadn't wanted to visit earth but he realized that he had unintentionally set London as a destination. He seemed so unfocused because of how tired he was. He shook that aside and focused on flying his ship.
"Allons-y!" he shouted. That line only brought a small smile to his face. But he was still feeling so lonely and sad.
The TARDIS flew through time and space. He wondered what time during London it would be, he figured it would be the 21st Century, landing the TARDIS he stepped out and looked around . As he figured it was 21st Century London.
There had to be something he could do to take his mind of all the pain. He wiped away the tears that he hadn't realized that had formed.