Had this problem myself, was never able to just fall asleep at night, it was always a struggle. Napping, never, that made no sense. I would usually fall asleep around 2AM, struggle to get up at 9AM, and would do catchup sleep until noon on the weekends. And this was with daily exercise, I was always very active.

About 10 years ago (mid 30s) I moved to a new city and pretty much had an empty apartment and nothing to do in the evening. Most importantly no TV or internet. I decided to just goto bed around ~9:30PM. I think because of the lack of stimuli or something, this stuck and I then found myself in a bedtime routine of falling asleep around 10PM and waking up around 6AM. I guess the key isn't to slip back into the old routine.

Fast forward many years and now I have a family. Not only am I passing out immediately at night, I also can take naps. Yes, im completely exhausted every night.