She's still alive.
This story is a sequel to Better Living Through Science and Ponies, the influential Portal crossover written by the talented Pen Stroke. If you have not yet read it, please do so first. (including the Reader’s Cut chapter)
After saving Equestria from GLaDOS' evil, Chell is finally able to live the life she never had... until GLaDOS sets in motion her plan to rebuild Aperture Science. It's only a matter of time before the experiments begin again, and only Chell will be able to stop her.
Now has a TV Tropes page!
Please note, this is an unofficial sequel. I have received permission from Pen Stroke, but it is not canon to the original. I hope you enjoy it, but keep in mind that this is a fan work (of a fan work), and Pen Stroke holds the rights to the original story.