I enjoyed this episode of Doctor Who very much when it first came out. Recently I had to revisit it, because I read that Steven Moffat wrote this as an homage to the book "The Time Traveler's Wife", which he liked very much.
The same theme is continued by Moffat later when he became the showrunner for "Doctor Who", with the character River Song. Her life pretty much parallels that of the wife in the novel.
The book's author had no problem with this. In fact in her second novel she has a character who watches this exact episode of "Doctor Who".
Here is what Moffat says about this:
"It's very similar in mood if not in detail. It's about a time-lapse relationship, and I did it quite consciously - knowing I was doing The Time Traveler's Wife. In my time on Doctor Who, I was more interested in the time travel aspect than most people probably are - I loved time conundrums and paradoxes. [...] She has a character in the book actually watching The Girl in the Fireplace on television, so I knew she was onto me. At which point I could be more obvious, so I made Doctor Who a wife - River Song."
The same theme is continued by Moffat later when he became the showrunner for "Doctor Who", with the character River Song. Her life pretty much parallels that of the wife in the novel.
The book's author had no problem with this. In fact in her second novel she has a character who watches this exact episode of "Doctor Who".
Here is what Moffat says about this:
"It's very similar in mood if not in detail. It's about a time-lapse relationship, and I did it quite consciously - knowing I was doing The Time Traveler's Wife. In my time on Doctor Who, I was more interested in the time travel aspect than most people probably are - I loved time conundrums and paradoxes. [...] She has a character in the book actually watching The Girl in the Fireplace on television, so I knew she was onto me. At which point I could be more obvious, so I made Doctor Who a wife - River Song."