Have you tried cutting out dairy? I cannot tell you the difference this has made for me in the past several months. Huge reduction in mucous!
So far this spring, I have not had to take any Zyrtec, nasal sprays (Q Var worked really well until the nosebleeds started and it is also very expensive until we meet our deductible), or anything else. I also got through the winter without bronchitis or sinus infections. I know how miserable you are because I felt that way from the time I was a small child. I hope you find some relief fast!