Gone are the old ways, and the good ol' days. What happens when you've forgotten how to speak, how to act, how to be 'civilized?' You reinvent yourself, and take what you can from the dead world. You've taken the scraps of memory left in the ruins, and from it, a new order - a new culture - has arisen. One that can survive the toxic air, the things that roam, and worst of all, other people.
When the last of your machines break down - when everyone's dying for a drop, you will thrive.