Hi Steve. Chronic bronchitis can be a lifetime condition as part of COPD (chronic obstructive pulmonary disease). While it is more likely to occur in smokers, non-smokers can also be affected. From what you report, there is no clear indication that this cough is originating from the lower airways. For example, you could have postnasal drip where the mucus from the nose passes backwards into the throat and irritates it. This can trigger a cough. Nevertheless, the cough along with your fatigue is worrying and needs to be investigated further. After seeing two doctors about it, it may be time to consult with a pulmonologist (lung specialist).