Yeah, ether cause you end up lacking life experience and sense that would keep you out of getting messed up (like telling a hungry peasant mob to eat cake) or cause you realize that everyone else have gotten messed up, and you start to feel disconnected from the world and the people around you.
Well. I am not going to say it is the only thing that fuels us, but it is there. The pain from hunger make us fight to get food. The pain from loneliness makes us build friendships. Pain is uncomfortable, so we try to learn from it, to avoid it. But if it comes, it can force us to what is necessary even if it hard. Hence why pain can make people do things they never though them self ever capable of, good or bad.