I discovered very late btw, that I don't have insomnia at all. I have DSPS.

I find it next to impossible to go sleep before my circadian rhythm says so, and it says so at 2am... I can't sleep for more than 5hrs either, and if I do for some strange reason, I'm super miserable and sluggish the next day.

I tried a sleep schedule/ritual, and am now able to sleep at midnight without being a complete b!tch the next day, but then I wake up at 4:30am, so it's kind of useless to do that.

The only time I have no problem sleeping before the window opens is when I'm exhausted, which happens about 2 nights a month, but not every month either.

If I miss the train to Lalaland, (00.00- 2:00), I will simply stay awake until it comes around again...
* on a side note, my mom tested this theory once, and I stayed up for 6 days. I was not very pleasant to be around.

I get my best REM sleep in the morning hours, so Saturday morning? Don't you dare wake me up!

My point? pills never helped me either, and when I adopted a sleep schedule and sleep ritual, to sleep more, my moods were even worse, and you mentioned being a nigh towl.
Maybe look at your sleep problems from a different angle and you may find a solution