I think I cured my headaches through breathing properly. Now I am trying to train myself to breath correctly all the time. All the smart Buddhist teachers I've met said that breathing is everything. I had headaches every day this week - due to stress, I thought; but it's been three days free of pain. I feel it coming on, and start counting and breathing deeply.
I hope this is all it is. That would be nice, and I am willing to accept that somehow, for the past ten years, I have been breathing wrong.