What if she had held on at the end? Post-Portal 2, slight AU, no humanizations.

Taking shelter from a thunderstorm, Gordon and Alyx find themselves stuck in a conveniently-located cabin. Gordon knows what's supposed to happen...and he can't afford to let it.

AU. Working at Aperture Science's top-secret research facility on the moon, a bitter, callous Doug Rattmann just wants to return to Earth, fed up with the monotony. But within the cold tedium, there's a spark of fire: a test subject with extraordinary tenacity. Drawn to her against his will, Doug finds that it's not too late for him to change, and that maybe he can save them both.