Coughing in public

No matter how often I use airway clearance, I still cough continuously. Out of respect for other people, I no longer go to movies, concerts, shows etc. It's hard even going to dinner or to friend's house.
Today I was in the grocery store coughing and the woman approaching me from the other end of the aisle put a hand over her mouth and nose and wouldn't even look at me. Last month, as I was waiting for my deli order, I stood at least 10 ft behind someone stifling a cough, but started clearing my throat. She turned around angrily and said if I had wanted her to move, I should have asked her. My reply was, "I wasn't coughing to get you to move, I was coughing because I'm sick.. but don't worry, lung cancer is not contagious."
Has anyone else encountered rude people like this? I certainly understand people are afraid of catching something in this day and age, but it makes me feel like nobody wants to be near me.