sorry if this has been posted before but is she dead? was that really her in the shrine? if so why did she stay behind, im just totally lost on that fact.
She has been dead, that thing is the Librarian AI. It is all that is left of what once was the Librarian. The Librarian AI is probably now gone with Requiem. The only other way The Librarian AI could possibly live on is through other AI fragments scattered across Forerunner mega-structures. Either that or she put herself in the key when she handed it over to Halsey.