There are no central authorities left, no governments, no military, no supply-chain, and next to no loyalty remains for anyone outside of your family or clan. Enough people with enough weapons can lay claim to anywhere - or anything - they feel entitled to unless someone is willing to try and stop them.
 
In a fractured country where territorial maps are being rewritten at a whim, you are going to have to navigate tribal lines and continually shifting threats as you look for your own place of safety.

Or maybe you will decide to just keep moving, dealing with threats as they arise instead of making yourself a sitting target.