Some thoughts:

Re: mental/emotional stress, yes it can cause tension in the muscles. It can also cause upper chest breathing which can narrow the space between the collar bone and first rib. Make sure you are belly breathing even when stressed. Furthermore, I notice that for myself and others close to me, stress generally aggravates just about any health problem.

Also, you might consider attacking the problem of stress itself more directly. An Amazon search for "stress" returns some well rated books whose explanations and exercises have helped people.

Re: exercise, there are studies that show that exercise can reduce pain. Here is one regarding yoga:

http://www.sciencedaily.com/releases...0727131421.htm

But I don't think boosting cortisol is exclusive to yoga. And there are other boosts too like human growth hormone.

For me, exercise makes me feel worse, but I have circulation issues in the neck area (which are gradually improving).

Re: computer work, if it is making you feel bad, make extra sure that you have *excellent* posture with no "forward head", "forward shoulders", "trap tension", etc. Just "sitting up" doesn't do it. I had to really study material on posture and study myself, and not compromise my posture at all.

But I still slump into bad posture when I get really engrossed in a project and, sure enough, start feeling bad again. Then I get up, stretch, straighten, do Brugger relief pose, relax and sit back down in good posture.

HTH