Yes this is a real issue. i hear that it was due too you starting at different days. If you look at you save, it will say X days resisted. i have started a game, and only played 10 mins and it says 55 days resisted.
You don`t get a chance to build up any kinda resistance. My 5 hour game, there were 10 man patrols running around wiping out all my gatherers, so I couldn`t build up my camps.