Hope things work out for you. It sucks being sick all the time for sure and I know how frustrating/depressing it is when you cant figure out a path forward.
Certainly recurrent sinus infections often require antibiotics ( I dont think you are an abuser) but dont underestimate the effect antibiotics have on you gut flora (and potentially your overall health). My understanding is that it can take you gut bacteria 12 months to fully recover after a course of antibiotics.
Another left field suggestion is Lyme disease. I am not sure of the prevalence where you live, but here in the North East it is one of the first things most doctors would consider. Symptoms can be non specific and the current test in not particularly accurate unfortunately.
If none of this works, drink more Whiskey. I find that always helps