constant muscle tension in neck and shoulders

I have constant muscle tension in my neck and shoulders and numbness in my hands. I go to the chiropractor when I can but can't go everyday. The only time these muscles are not tight is when I consciousley think about relaxing them,as soon as I stop thinking about it they go right back to being tight.This has been a lifetime problem but now that I am older it's getting really difficult to deal with the pain.
It's a daily problem!