This happens to me, too. My workload has tripled since I was hired and I'm on call more than twice the amount of time they told me I would be when I'm hired. I fortunately don't have to put in more hours typically (sometimes); I just try to work much faster. But my office is FULL of workaholics.

Is it possible for you to bike commute to work? Then at least you'd get a ride -- and you could possibly take a ride at lunch, too.