I may have mentioned I suffer from migraines. Technically, they are "chronic migraine headaches" in that they occur nearly every day. To get an idea of what these are like (for you blessed people who never suffer from them), go out and find a bench vise big enough to hold your head. Do not mount it to a bench, just turn it upside-down over your head and start closing the vice. When you finally are experiencing about as much pain as you can stand, close the vice another half-turn. Now, go about your business, wearing the vise everywhere you go. Can you feel the muscles in your neck begin to tighten? Starting to feel the burn in your shoulders? Congrats...now we have something in common.
You hear the phrase about not wishing something on your worst enemy. I didn't know what that really meant until I started to have daily headaches. But I do now, and there is nobody I know I would wish this upon. It's just too horrible. I frequently meet people who suffer migraines (a few of them chronic, like me) and there's a kind of connection between migrainers, not that much different than that which binds Harley Hoggers.
A pair (or group) of migrainers get together and trade info on what has worked, and what has not; which doctors are better at treating the pain; recipes for various dishes (some migraines have a food component that brings them on...most commonly red wine or food that has sulfites...for me, it is vinegar of any type); over-the-counter remedies; books, music and things to help soothe the pain. It is very helpful to know you are not alone.