Lena does approach 76, looking up and down in disbelief. She hasn't even thought about what his status of living means for the recall, especially in the context of what he's been doing. All she can presently process is that Jack Morrison is alive and in front of her, and that he's been living alone in relative silence since the explosion.

Whether or not she hears his correction on his title, its not clear.

"Why?"

Its the only thing that comes out of her mouth at first, quiet and hurt. 'Why' encompassed so many of her questions -- the most important ones, anyway. Its clear she wants to reach out, to touch and verify that she's not imagining things -- that this isn't some strange hologram messing with her.

"We all -- I thought you were dead."

She skips the 'sir', so it seems she took some of what he'd said to heart.