I have had a chronic headache - constant 24/7 - for 4 years. It began with a sinus infection for me and has never gone away. I have tried every therapy and drug I can think of, without help. Fortunately, it is not entirely debilitating. It is a dull ache that only becomes problematic at work when I have to think. ha. So, I try to avoid stress, and I've had to psychologically deal with the fact that this may never go away.
I'm sorry I have no recommended course of action for you. As with others in chronic pain, I am propelled onward by a need to define my ailment (most likely New Daily Persistent Headache) and to find new treatment methods. Keep at it. Something may eventually work for you.