What can cause long term chest congestion and coughing?

[Aquaticdeity]

I got sick in December and ended up with bronchitis which was treated with steroids and antibiotics. I went through that dose and 2 more after, also was given an inhaler.
I dealt with that for months and visited the doctor multiple times until I finally went to a pulmonologist. I had 2 chest x-rays that showed nothing and he couldn't find anything either. They tested my breathing and it was fine, so no asthma our any other obvious causes. I'm at my wits end because everyone I seem to be getting better I end up with sinus issues that seem to trigger it all over again. I can't even buy myself claritin or zyrtec D at the pharmacy because I've bought it too much. Nothing seems to help. Musinex seems to make my coughing worse. If anyone has any tips I'd be grateful. Or even a holistic approach. I'm just sick of being sick....