In buddhism, focusing the awareness on one's breath is central to meditation. And in this book I read called "The Relaxation Response" the guy shows how deep abdominal breathing can reverse panic and relieve anxiety.
All the time I am trying to focus on my breath to calm myself. I never considered it could be the source of such stress. Maybe if you could stop fearing it, you could use that concentration to your advantage?
Anyhow, I hope you find peace with your breathing, and learn not to view it as a limitation, but a blessing.
Good luck.
