Mark my words. Corty's death was ambivalent. She was in a Forerunner environment and you didn't exactly witness her croaking. The way the Forerunners digitized humans is the way she'll "humanize" herself. She and Chief will wind up together on a tropical island as two humans. As for OP crying, I cried more (as in some) when she said, "You found me." 4 is heavily related to 2's making of promises and AI sacrifice. No harm here. I guess I'm the "good" forum cop.