The Doctor had to try to find a long term companion because he had a few in this regeneration that he can’t recall what he told Rose. Also, all the companions all seemed wanted to know where he is from. Why do they want to know? Oh, he told himself humans. They are a curious bunch of monkeys.
He had Rose Tyler, Martha Jones, Donna Noble as companions. He had Jack Harkness around. He had connections with UNIT, Torchwood, Sarah Jane Smith and a few others. They all seem to want to know about his place of origin.
He had many people who he had worked with and they all died working with him. Humans can very noble and throw their life away just to give him that chance to succeed on saving Earth and time and planets and the Universe. So, many died. He would admit he could never do it alone. People died for his success.
Now, Rose was asking where he came from. No, what time he was from. How can he explain that? Why does she want to know? He thought of his human self in the other dimension. He wondered how he was dealing with Rose Tyler there.
He had thought of his future wife. He doesn’t know when he will meet her but surely there will be a cost. There always had been. He can take a guess it’s not this regeneration. He had to die first and regenerate and he will see her. So, he thought.
So, the Doctor stood there with a deep sad look as he was drawing on the past. The switch of depression was on. Funny how one question had brought him thinking on all of that!
The Doctor's sneakers are getting soaked by the ocean. He didn't seemed to care. It was like he just had turned off his awareness off. It's so alien.