I would suggest that people are completely responsible for their own actions but that society needs to do what is best for itself even if that means getting people out of holes they did through their own mistakes.
The prime example of this is the recent financial crisis and the various bailouts. Should the government have let the automakers go bankrupt? If we want to hold people responsible for their actions, yes. But then what happens to our economy as a whole? Is it worth it to get the pleasure of punishing the car companies (or the banks or the people who took out mortgages they couldn't afford) if it means that our whole economy goes into an even bigger slump? I would argue that that would be a mistake.
In a perfect world, everyone would get their just deserts. However, we don't live in a perfect world and sometimes we need to rescue people who make mistakes to preserve the greater good.