I was going to suggest Zyrtec but I see you’ve tried it. It knocked out my springtime allergies like a miracle drug. One day sneezing continuously, took one and the next … NOTHING. I worship the god Zyrtec.
We don’t use a neti pot; we have an attachment on the WaterPik shoot it up our noses that way. Clears you right out, and hydrates the nose wonderfully. I recommend it to anyone who suffers from dry nose when pregnant, which I did with all of mine. I felt nicely watered the whole last pregnancy.