Hello and hope you are doing well.
The other causes for long term cough besides asthma are GERD and post nasal drip from allergies. GERD is gastro esophageal reflux disease where the stomach acids come back into the esophagus and spill into the wind pipe causing cough. Treatment with antacids will help neutralize the acids. Post nasal drips can occur with sinusitis and throat infections. Giving up cigarettes will abolish smoker's cough in 90% of people. Talk to your GP about the other causes for cough in the meantime you could try warm salt water gargles and breathing exercises.
Hope this helped and do keep us posted.
Sorry to read about your stressful condition... I have not read the other threads on this subject. So, I wonder if you have given an very careful consideration to what was going on in your life/environment 5 months ago when the cough started? Something must have triggered it, and maybe it is still around..something new in your home, animate or inanimate, think back even if you already have. Any discussion with a doctor should include accurate information about how you fell, when it started, any other changes... must be other important things.