“It’s 2017 nobody wants to hear Portal meta”
The prevailing ideas in the Portal fandom seem to be the following: 1. that Cave and Caroline were romantically involved, and 2. That Caroline was made into GLaDOS against her will.
First of all, it seems to me that Cave and Caroline had more of a father-daughter relationship than anything. Caroline is markedly younger than Cave, and Cave treats her with the sort of doting fondness one would expect from a father or father-figure. He’s more her mentor than her partner. This will become important later.
Secondly, let’s review the dialogue:
“If I die before you people can pour me into a computer, I want Caroline to run this place. She’ll argue, she’ll say she can’t, but you make her.”
Cave wants Caroline to take over for him after he dies. Now this seems … odd, in the context of the time period in which that dialogue was spoken. Why Caroline, who has been hovering somewhere between secretary and nurse for the past 20 years? Why not any of the other qualified scientists?
Because Cave views Caroline as his successor, almost his progeny. He sees her potential because she’s been working closely with him for 20 years. There’s no talk of turning her into a computer; just that Cave wants her to run Aperture after he’s gone. (Behind every great man is a woman rolling her eyes, etc.)
But then Caroline does take over, and it’s obvious that she makes some drastic changes to Aperture. It must have been immensely difficult for her, being a woman in a position of power in such a male-dominated field. The scientists probably fought her at every turn. She wasn’t getting any younger, and she was perhaps made wary by her mentor’s untimely demise.
So Caroline pushes the AI initiative at Aperture, and eventually makes herself into GLaDOS.
Now imagine: you suddenly find yourself an omnipotent, omniscient demigod, surrounded by the men who have been forcing you to fight tooth and nail for every inch of progress. Well fuck them, they can’t stop you anymore. You run this place. You are this place.
“The scientists tried everything to make me behave. To slow me down.”
Because despite everything, GLaDOS is still a woman, and that’s what men do to great women. Make them behave, slow them down. Still, even now, even when she’s transcended humanity, surpassed all of them, they still won’t listen, they still won’t leave her alone.
In that position, it’s completely unsurprising that she murdered all of them.