Insomnia Support Group
Insomnia is a symptom, rather than a disease, and is characterized by inadequate quantity or quality of sleep. People with insomnia complain of difficulty falling or staying asleep, which results in significant impairment of daytime functioning. Insomnia is categorized as transient (shorter than one week), short-term (one to three weeks) or chronic (longer than three...
I went through an episode earlier this year like you describe. It was a solid month of 2-3 hours of restless, fragmented sleep per night. But somehow I felt sort of OK and could function just fine during the day. I mean I still felt fatigued somewhat, but did everything I usually do, including work ,exercise, etc. And tried to keep the same sleep schedule.
What that showed me is how well our minds and bodies compensate for sleep deprivation, and I by no means think I'm unique. If you are "fine" like you say, this suggests you too are compensating.
My suggestion would be to try to get to the bottom of this, and drugs do not sound like a good solution for you. So that leaves nondrug solutions, and there are plenty to consider.
You can try a consistent sleep schedule, and only allow the minimum time in bed you think you need for sleep. And no more. That should help rev up your sleep drive.
Daily exercise, both physical and mental, to tire yourself out.
Watch caffeine in all forms after about mid day.
Plan a relaxing wind-down period before bed. Minimize stress during this time.
Continue to use relaxation and distraction methods in bed. There are dozens of ways to do this. If what you've tried so far isn't working, continue researching other methods like guided imagery.
Perhaps most important in your case might be to comprehensively address stress and anxiety. What you are experiencing could be a hyperaroused state due to excessive levels of stress and anxiety, and particularly about the idea of sleep.
Are you getting counseling? What are you doing for mental health treatment?