What exactly happened between GLaDOS and Wheatley while he was one of her cores that makes her hate him so much? And why don't they seem to remember each other until the last second? Things may not have gone the way they seem to have gone... Prequel to Love as a Construct.

After the events of Portal 2, GLaDOS brings Wheatley out of space to keep her company. Through trial and error and revelations, their friendship grows into an undeniable connection that they just might be able to call love. And with that on their side, they can do just about anything... maybe even save the world. No humanisations or androids.

They called her Mom just because they knew how much she hated it.