My daughter just got over it. She had been coughing for a long time at night but I was asleep and didn't hear her. She had no fever and was going to school and going to swim meets etc. She even went trick or treating in the snow on Halloween. One night, I heard her coughing and something wasn't quite right. Turns out that she had mycoplasma pneumonia (walking pneumonia) and had to take a z-pack. However, her cough refused to go away so she had to take a second round of antibiotics which apparently got rid of it.

Anyway after the second round of antibiotics she got a sinus infection and went on her third round of antibiotics which she finally just finished.

She is coughing again and I'm paranoid that even with all the antibiotics she too, she still has it. I totally feel your pain. It's a tough thing to shake!