Tears of steel 24/7 DVR

Thom just wanted to be an astronaut. His girlfriend Celia just wanted to create robots - and for him to not be freaked out by her cyborg hand. How was Thom supposed to know that breaking up with her would make her take out her anger on the rest of humanity using her robots? It seems the only possible way of undoing everything...is to overwrite her memory of what happened 40 years ago.