if going to bed at the same time / getting up at the same times works, then you're probably lucky to not have such an extreme disorder. I've tried this and it doesn't work for me, the only solution has been to change my life so it fits more around my condition. This is through a combination of - 1 part time job, 1 teaching job and a number of freelance jobs.
Freelancing is probably your best option as you can work from home at hours that suit you, the best way to get freelance work is via direct contacts, get yourself a linkedin profile & your own website (if you don't already) and get networking. Most of my freelance work comes from word of mouth, so make sure as many people as possible know what you do & that you're available.
Contracting is an option, as you could deal with the sleep deprivation for a couple of months, then take a couple of weeks off - there's loads of agencies about, just make sure you 'sell' yourself to them with a really great CV.
Alternatively, do some research and find a company that promotes more progressive working styles, I worked at one small agency which allowed people to work from home if they chose, or work shifts at the office that suited them.
Don't give up hope, it's not your fault you have this condition, and if workplaces' could be more flexible it would be better for everyone that's currently excluded (i.e. people with disabilities, single parents, etc).