As I see it, you can think through and prep for a specific TEOTWAWKI scenario but you will never be able to prep for every possible circumstance. There will always be some unforeseen factor which modifies the scenario in such a way as to render your prepping less useful.
In any situation, however, there is one resource which is going to be very precious indeed and you can start increasing your share anytime and all it will cost will be your time and maybe a dram or two. That resource is people and more specifically, friends. When it all goes up, will there be anyone out there who will lend or give you what you need based on goodwill alone?
Z