and lemme tell you something

1) at the very beginning of the game, when the protagonist is asked by Hadvar "who are you?";

2) when Harkon asks the name of his daughter's saviour;

3) when they introduce themselves to Lucien;

4) in thalmor embassy during the party (optional).

Now hear me out

Kaidan and the ldb have been together for a long time, has gone through only god knows how many ordeals, almost facing their demise and well... Kaidan still has no clue of his spouse's name.