That's unfortunate. Perhaps you might consider a change in careers? I'm working on a project now that wasn't oversold on what the product would do, nor the timeframe. In fact, when I sold it (or rather, sold myself to work on the project), I told them straight up that a) I don't know how long it would take to build, because it would take a lot of trial and error research (but would likely be a minimum of 6 months) and b) that what the product would do would be built up gradually, so that every time they got a new version, it would be useful for them, so that they could give timely feedback and adjust priorities. So far, I've delivered exactly what I've promised, all while working 40hours (or less) per week. But then, I like to be honest.

Interestingly enough, for the previous project I worked on, my boss tried to "oversell" the (internal) customers on how little time it would take (6 months) when they knew (and had told my boss) that it would take a couple of years with multiple people (they'd helped develop a similar project before). When I started, I told them that I'd never worked on a project of that scope before, nor worked with any of the technologies they were requiring me to use. They were cool with that, were pleased with my rate of progression, and told me more than once that they had no realistic expectation that I'd be meeting the schedule laid out by my boss.

Sounds like you live in the Dilbert world. I can assure you that the entire software development/IT world isn't like that.