Zombie Apocalypse.

While unconscious, your rival team mates grab as many supplies as they can and escape with one of the vehicles. Perhaps killing the distant figures without checking to see if they're survivors was the straw that broke the camels back, and they didn't want to be associated with you any more. Alarmed, you get up and realize that they'd left. With only a few of your trustworthy partners remaining, one vehicle, and a miniscule amount of supplies, you conclude that it would be futile to try to run after them. You're already weak and sleep-deprived. Reluctantly, you and your remaining team retire for the night.