It sounds like you have chronic sinusitis. The fact that you got better, briefly, on antibiotics makes this more likely. The good news? Brain tumors etc don't get better on antibiotics ;)
I think that you should consult with an ENT physician and, if she thinks it is indicated, get a MRI of your sinuses. Treatment may need only nasal decongestants and therapy. If that doesn't clear things up then surgical treatment should be effective.
Doest this make sense to you?
I just got your post....and, no. I do not think that you need to suffer with this all summer. Nor do I think taking another course of antibiotics is the way to go. You need to get to the root of the problem and, to do this, and ENT doctor is your best bet.
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