You have my sympathy. Over many years I have developed an unhealthy sleep routine myself.
I find that, for some reason, I am very alert and productive in the hours after everyone has gone to bed. No doubt the silence and absence of email/phone distractions is a factor. However, my reasons for staying up late were not because I couldn't sleep. Actually I have always been blessed with the ability to fall asleep quite easily.
No, the reasons for regularly staying up until 2 or 3 am (or later) were, and are, professional. Since I work for myself, with a client base that draws from all time zones, I got into the habit of trying to make sure that I got as many project deliverables over to my customers every night, so that they would have them "on their desk" and be able to respond whilst I was asleep. The alternative, for some client locations, was to "lose" two business days.
Since "Time = Risk", especially where you are running your own business, in the development stage I got into the habit of regularly working into the early hours in order to minimise the delay factor.
I am slightly better know, and don't pull an all-nighter so often. But even so, there are still some days where I will only catch between 3 and 4 hours sleep in order to get stuff out.
Coffee works wonderfully to keep me going Monday through Friday. Being something of a connoisseur of the old bean juice, this is not a hardship. And I am fortunate that I do like what I do, so that also helps keep me focused. Furthermore, I always take a break between 4 pm and 10pm, so I can be with my family, eat with them and catch up on TV.
There is one more thing that keeps me sane - sleeping in at weekends. I sometimes think the idea of "brunch" was developed just with me in mind....