In an apocalyptic scenario, where civilization has broken down (insert asteroid strike, zombie apocalypse, global thermonuclear war), would you rather gang up with other survivors, or try to make it on your own?
My participation in any group would be limited to my own benefit from such a group. I wouldn't take up anyone's flag without assured benefit of my own.
My family and very close friends that's it
Solo is a short-term strategy.
Group...strength in numbers & that would offer a better chance for survival. Combined, there would be a greater knowledge base, greater variety of skill sets, and more physical strength as well.
I'd try to arm myself well then head for the wilderness and wait until some semblance of order is restored.