> I get a kind of arthritis in the back of my
> neck when I drink too much.
If you have a sore stiffness on both sides of the back of your neck and sore spots in the middle/back part of your shoulders these are serious warning signs of the early stages of fibromyalgia.
Take care of your sleep. Stop coffee altogether and change your lifestyle to reduce sleep problems and stress.
Once it really sets in it will never fully go away.