In addition you've tried:
• phenibut (post #4)
• a fan blowing on you (post #6)
• white noise and acupuncture (post #7)
• iodine and selenium (post #10)
• benadryl (post #11)
It's a bewildering array of suggestions.
It's a shame you can't take the cold. It seems there's been some success getting insomniacs to sleep by providing them with chilled pillows. Those seem to be on the market now.
I liked the long list in post number #3. I wondered about this one: "9. Learn meditative breathing". Could you re-visit that even if you've done something like it before? Not necessarily the breathing but some kind of meditative technique. You might experiment with these guided meditations that combine the "being still" aspect of traditional meditative techniques with binaural beats. They have apparently sent off a few people who have had trouble sleeping. Episode 1 might be worth a try, or episode 14, which is specifically aimed at sleep:
The Meditation Podcast - learn to meditate, guided meditations, binaural beats - free download or subscribe in itunes
Or a more traditional technique like mindfulness meditation might help.
Here's an off-the-wall suggestion. I don't know whether it's ever been used for insomnia, but how about neurofeedback? It seems to be capable of re-regulating many brain functions and an impressive array of general biological responses. It's even been used with success with some previously highly intransigent problems like alcoholism and combat stress. It's not cheap, but if it would work for the purpose -- which is what I don't know -- it might be worth the cost. Among Paleo people, I know Nora Gedgaudas uses it. She seems quite approachable: maybe you could drop her a line and ask if it's ever been used for insomnia:
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