I'm sorry you are also experiencing excrutiating nocturnal headaches. Have you visited a headache specialist (usually a neurologist who specializes in headaches) to obtain a diagnosis? It sounds sleep induced. NIH discusses nighttime headache types adn causes which help elucidate "best" potential treatments and preventatives. Here is the link to their article: https://pubmed.ncbi.nlm.nih.gov/24132786/ Have you already tried drinking a cup or two of coffee at night prior to bedtime? Or taking caffiene pills (less liquid!)? Melatonin alone even in high doses did nothing for mine, either. For my particular case, it takes a combo of preventative Indomethacin plus coffee plus 30mg melatonin nightly to prevent the nightly headaches about 98% of the time. My headaches are undetermined as they don't fit the category descriptions for hypnic or clusters (four times nightly, at exact same times REM sleep intervals), but they appear to be sort of a combination of the two. Chronic recurring pain and lack of sleep can be so depressing. I hope you can find help and some good solutions.