Something I always try to [gently] instill upon the interns is that if you break your back for the company, the only thing you will get is a broken back. The company does not care. Even if on some level the people in charge do care about you, they care more about money. The day that they stand to make more money by firing you than by continuing to employ you, you’ll be gone.

You are nothing but a name and salary on a spreadsheet. And if you’re wise, that’s all your employer should ever be to you.