: Cortana mentions it on Composer (the second-to-last level) after you put her
: in Ivanoff Station's defense grid and take her back out (something along
: the lines of "if we actually find Halsey and fix me, don't tell her
: how bad I got").

Ooh yeah, I had forgotten about that. That was actually one of my favorite lines from the game. Seeing Cortana ashamed of herself in more than just a "concern for her life" kind of way was really impactful. We see that she really cares what Halsey thinks of her and that in a real way, wants Halsey's approval. It also furthers the Chief-Cortana bond by having her confide her insecurities in him. The Chief is privy to Cortana's intimate details, but Cortana doesn't want that to extend to anyone else.

I really do like what they did that relationship during Cortana's descent into insanity.