I think in your situation the answer is to start looking for your next opportunity now. It may take you a while to find that next gig and during that time you will have a little longer to evaluate / make changes to your current opportunity.

It sounds to me like you have also learned something; a lean mean start up where you have to live paycheck to paycheck is not the best type of environment for you to operate in. If finances stress you out then I am sure they are negatively impacting your work and personal life. I strongly suggest when looking for that next gig make sure you get a position where the wages will be enough that you don't have them as a source of continual concern.

Tons of startups fail for any number of reasons, walking away from 6 months work shouldn't overly bother you unless you believe strongly that the startup is close to turning the corner. Define turning the corner in whatever sense you need to - creating a great product, getting funded, becoming ROI positive without funding, etc.

Finally remember sometimes you will do more good by leaving than you ever could have by staying. If the technical process is making you insane, it might be best for you to go and for them to get someone else in who might be able to unmuddle the situation. Either way there is no shame in leaving, just be sure not to purposely burn any bridges when you do.

Best of luck with your decision.

"but then again, I'd be walking away from six months of work"

This is known as the Fallacy of Sunk Costs (http://en.wikipedia.org/wiki/Sunk_costs). While it's very hard to view such a situation dispassionately (I know from experience), you should at the very least ask yourself the classic question: Forget about the past. What will future investment (continuing to work for this train wreck) bring me?

Insanity and madness, from what sounds like true capriciousness, do not recommend themselves.

"nothing to show for it thanks to the NDA"

Perhaps you can, as a condition of your giving them two weeks notice, negotiate for the release of a few code samples that don't reveal anything secret or terribly useful about the company? Building up a portfolio of these sorts of things is a good idea, I have one that's about 1/2 thick showing everything from code, design, documentation of both and for users, etc.

You probably should have left a long time ago, from the sound of what you're saying.

Main thing to keep in mind (and that people too often forget in situations like these) is that you don't owe it to them to stay in this job. If something in your gut is telling you that what you're doing isn't just isn't right, "it's insane", killing you financially... then it probably is.

Another thing to keep in mind is that it's much better to quit and have nothing to show for 6 months of work, than... to get fired / laid off and have nothing to show for 6 months of work (and/or possibly not getting paid for the last several weeks of this.) Get my drift?

So it's up to you to "do the right thing" here. You'll wait until finding another job before giving notice of course. But the main thing is to do what's right for you, and on your timetable, not theirs.

See also:

    http://en.wikipedia.org/wiki/Stockholm_syndrome

What is your time worth? Generally startups seem to have a fairly common lifecycle (at least in the embryonic stages). Vision -> work to prototype/proof of concept -> { Seed | Exit }. If it is not self-funded the founders should have talked to at least Angel investors, they should have a list of questions that investors have been asking them prior to deciding to invest, and they should have a plan for answering those questions. If they don't, then they may have lost their way. If they are lost then staying is a waste of your time.

Thanks for the advice. I've started the process of hunting for something else. I'm not going to burn all my bridges at once, but I definitely want out quick.

Further note: I'm a coding grunt and I like it that way.