Thanks for all the suggested. Various remedies tried and tested and only two had any effect.
The first were Potters Chesty Cough thingmies. I think these worked to a certain extent because the actual sucking helped stop the cough reflex for a while and there was some sort of foul tasting substance in them that seemed to help loosen things 
And I invested in a humidifier which I took into the bedroom at night and the living areas by day. So yes, steam has helped. If I had a bad 'do' I'd lean into the stream and inhale. Yes, steaming water plus things in a bowl is one way, but I couldn't be getting up in the middle of the night, going downstairs, boiling a kettle, etc. so the humidifier was there when neeeded.
Still coughing but at least it's not as painful any more, I'm sleeping better and energy levels returning slowly.