I used to have the same problems as you, the exact same problems as you just described. I mean this without malice, are you sure you haven't diagnosed yourself with something funky when you're actually just bad at preparing for sleep?

Using f.lux, exercising, no caffeine past 5 and establishing proper sleep hygiene fixed it for me, but it took me till my 30s to figure it out. Drinking alcohol seems to be very expensive on sleep cycles. With exercise I also found I needed to do it before 8pm or I would often still be very awake. The other thing is meditation to calm yourself down, I found that sometimes I would be breathing very fast when lying in bed, turns out I was wired still.

And when I slip, I'm back to finding it harder to get to bed on time, 12:30, 1am, 1:30am, 2am, problems start with getting to work on time. Having to catch up at the weekends, sleeping till 12. Finding it incredibly hard to get going on Mondays.

I also found when I had slipped with correct bedtime, melatonin helped me reset my sleep clock back to midnight. Taking it just one or two nights 45 mins before bedtime, will help me get back to bed at a right time. Apparantly the standard dose is 10x what you actually need (300 micro-g is enough, rather than 300 mg). I only use it once every few months.