Well GLaDOS might be just Caroline.
The turret group that sings at the end says in Italian:
Cara, bel, cara mia bella, la mia bambina, oh Chell, che lastima, che lastima, deh! Cara mia, addio! La mia bimba cara, perchè non passi lontana, deh si lontana da scienza? Cara, cara mia bambina, ah mia bel, ah mia cara, la mia cara, la mia bambina, oh cara, cara mia....
But when translated in to English:
My dear, beautiful darling, my child that i admire.
To my dear, farewell! My dear girl, why not walk far away from science?
My dear, dear girl. To my lovely. To my dear. To my dear. To my child, My dear, dear to me!
So did GLaDOS really delete caroline?