It's the crazy ones that survive.
The ones that believed in conspiracy theories and had safe houses and escape plans and food packs stored in strange places. The people who knew that the world wasn't quite what it seemed but didn't know what else was out there.
The ones that were prepared for anything.
Even an alien invasion from the inside out.
It's the crazy ones that live, which is how Jeb has managed for so long, in spite of the Souls hunting down the last remnants of the human resistance.
So he may be crazy, but he's damn glad for it.