Good Afternoon,
I am sorry to read of your continued issues and wondering if you have ever been tested for allergies?
We all secrete mucus that helps lubricate and protect the esophagus and airways from pollutants. If you have allergies, although not rated highly on the Skin Test, anxiety will cause the body to react to any problematic stimuli by fighting it off with the only way the body knows.
In your case, mucus secretion is what will stop the "predator" from harming you. It doesn't have to be stress. It can be a form of diet which one ingredient consumed everyday causes this reaction. It can also be a slight allergy that you can't escape from will also increase the likelihood of excessive mucus.
A balanced diet, limit caffeine intake, and low sodium consumption helps relieve the symptoms. Drinking 8-10 glasses of water is not just a USRDA fact, it's the rules in this game. The more your body is hydrated the thinner the mucus will be. Caffeine dehydrates the body which causes thickening of mucus. High sodium cause higher blood pressure. Consider making changes in your diet.
Once you get to the point you feel confident enough to comfortably exercise, the body's natural endorphins will help out by making the body feel good.
You will win this battle. Your body might have control now, but once all those tests show that physically you are fine, then the only solution is mental. Don't let anyone say that you are crazy and all this is in your head because although it may sound like it, it still is physiological. It's just a physiological reaction, caused by a psychological stimulus. Resources:SteadyHealth
I wish you peace,Kitt