Your question intrigued me so much that i searched for books on Amazon dealing with "Headache" and to my surprise, there is a whole lot. You might want to try a

Your question intrigued me so much that i searched for books on Amazon dealing with "Headache" and to my surprise, there is a whole lot. You might want to try a couple; the book Splitting: The inside story on Headaches by Amanda Ellison (https://www.durham.ac.uk/staff/amanda-ellison/ https://www.durham.ac.uk/staff/amanda-ellison/) seems promising.