Sorry to hear of your long journey with headaches. I have had constant severe headaches for thirteen year. Also in both temples. I too have tried all kinds of meds, treatments, doctors, specialists, etc.
Your neurologist could do a lumbar puncture and that will tell if you have low pressure before going ahead with the more invasive treatments.
I am now awaiting a surgery date to get an occipital nerve stimulator. You can google this for more info on it. You could ask your neurologist for a referral to a neurosurgeon to be assessed to see if you are a candidate for this. Where do you live? this surgery is done in many states. Also if you are interested I can hook you up with a facebook group of people who have had the surgery or are in the process of getting the stimulator. Let me know.
Have you tried any pain meds? chiropractic? massage? orthodontist to rule out tmj disorder? pain management dr? nerve blocks?
Keep posting. I would also suggest you come to the chronic pain forum. This forum is very active with a lot of support and a wealth of knowledge. That is where i always post, so hope to see you there.