GLaDOS: Oh, thank God you're all right. You know, being Caroline taught me a valuable lesson. I thought you were my greatest enemy, when all along you were my best friend. The surge of emotion that shot through me when I saved your life taught me an even more valuable lesson - where Caroline lives in my brain.

beep

Announcer: Caroline deleted.

GLaDOS: Goodbye, Caroline. You know, deleting Caroline just now taught me a valuable lesson: the best solution to a problem is usually the easiest one. And I'll be honest. Killing you? Is hard. You know what my days used to be like? I just tested. Nobody murdered me. Or put me in a potato. Or fed me to birds. I had a pretty good life. And then you showed up. You dangerous, mute lunatic. So you know what? You win. Just go.

GLaDOS starts Chell's elevator moving up; she laughs softly

GLaDOS: It's been fun. Don't come back.

There should be a portal device on that podium over there. I can't see it though. Maybe it fell off. Do you want to go and have a quick look?
Whoah! Hello? Can you see the portal gun? Also, are you alive? That's important; should have asked that first. I'm - do you know what I'm going to do? I'm going to work on the assumption that you're still alive, and I'm just going to wait for you up ahead. I'll wait - I'll wait one hour. Then I'll come back, and, assuming I can locate your dead body, I'll bury you. All right? Brilliant! Go, team! See you in an hour! Hopefully! If you're not - dead.

It's not like I have hordes of replacement monitors just lying around back here in the old warehouse that I can just wheel out and bolt back on. I didn't order in loads of spare monitors thinking some crazy woman was going to go around smashing them all. Sorry if that's my fault. Sorry if I didn't have the forethought to think "oh she might go crazy one day and smash all the monitors instead of just getting on with things". Sorry I didn't think of that.

If the rules of physics no longer apply in the future, then god help you.

It's not out of the question that you might have a very minor case of serious brain damage.