[She wants to ask more questions and she probably will eventually but right now the amount of pain the Doctor was in in the memory is curtailing the questions. She doesn't want to cause him anymore pain. She sort of mumbles an apology, the sort of 'I'm sorry for your loss' kind of thing. She'll get to her questions eventually. For the moment his diversion works. She gives him a sort of furrowed brow and there's a hint of guilt about her expression when she shakes her head.]

We used the TARDIS as a power source and a navigation, ran the power through a circuit. She was trying to find you, tellin' us sort of the coordinates. Those got put into a computer, the computer told the circuit where to send...when Donna showed up, it used her to find where she needed to go to change her own mind, her decision so that it lead to you. Why?