Thanks Ian and John.
I've been running/interval type of training since the beginning of February and mixing that with boxing/boot camp style exercise classes. My wife got me onto them.
I will say that my coping mechanisms are still re-wiring and stressful situations aren't easy to deal with on occasion. Not all of them but some. I find that my sleeping patterns are the first thing affected which just makes everything that much more difficult.... I really do need to look into some proper meditation techniques.
As part of this I have also quit caffeine and cut down my sugar intake considerably (processed sugar entirely). Has also made a huge difference!!
It hasn't been easy though and I have thought about returning many times. Each day as it comes but my resolve is strong - I just feel so much better physically - it's great not coughing all the time