Suggest Treatment For Severe Insomnia

my husband has terrible insomnia (from fibromyalgia) He takes benadryl, 5htp, melatonin, magnesium, lithium salts, eats low carb, drinks hydrogen water (diluted 35% food grade). Are any of these causing too much serotonin or interacting negatively? He also ordered blue ray blocking glasses. He and I have both researched and tried a ton of stuff! Also substituted L-tryptophan for the 5htp and sometimes interchange the melatonin with valerian root. He does not take any prescripts. That what put him in this mess to start with....