Factual error: The President's casket is being brought into hanger at Dover AFB Delaware. There are no mountains in Delaware as was seen in the background.
Factual error: At the beginning of the last sequence a city centre is shown with the caption "Moscow." In fact, the city shown is Budapest, with the Danube, Castle, St Matthias Church, Fisherman's Bastion and Chain Bridge visible.
Chosen answer: Everyone else calls him Brody or Sgt. Brody, and it probably became habit to her.
The_Iceman
Can't get the source but I read that even the Producer responded to that. Stating that it was common practise for a military wife living in a military complex as everybody refers to their husband by their last name.