For as long as I can remember (even dating back to childhood) ive never had a consistent ability to maintain a sleep time. This has resulted in me always being tired. I remember in elementary school over the summer I'd fall asleep at 4am and wake up at 12pm. In high school I would sleep at 4am, wake up at 8:30 for school, then sleep the second half at 4pm when i got home. Earlier this year I was sleeping at 3 in the afternoon until 11pm at night, then I would stay up all night and go to work. Today I fell asleep at 7pm or so and woke up at 2am, just been watching a show and listening to music since then while waiting to get ready for work. Often times if I try and maintain a specific time of sleeping I will roll around for hours awake, or alternatively I will only sleep for a few hours and then fall back asleep later. The longest ive been able to manage a consistent sleep time was in 11th grade, for about 6 months I slept at 11pm but gradually my body started wanting to push later and later. I tend to only get a full 8 hours of sleep one or two nights per week as well, sometimes I'll drink alcohol to help sleep longer but only on a friday or saturday.
You might be interested in trying a polyphasic sleep cycle. Instead of one big 8 hour sleep each day, you could try two 4 hour sleeps. So, you can have your middle of the night sleep, and maybe another one after you get home from work or eat dinner or something.
Supposedly polyphasic was pretty common prior to the industrial revolution. Nothing really wrong with it if your schedule can accommodate it.
oh wow, this sounds exactly like how I was sleeping in high school. I remember back then reading about something called biphasic sleep. maybe I'll try and go back to something like that.