Sounds like you've already tried just about everything. But, trite as this advice is, you just have to keep trying. I still push sinus rinses (lots of them, not just two a day) as I know they helped me. Even when one or both nostrils were completely blocked (this was often the case for me), I would still try and would seize the opportunity when things were more open. (Don't use more than gentle back and forth pressure with the sqeeze bottle, though, as that can do damage.)
Apparently you had surgery years ago and it did work for a time. You might have to consider it again. The good news is that they have a new "balloon" sinuplasty (?) procedure now that is less invasive. Do some Googling if you haven't heard of it.
As I well know, these chronic sinus infections are nasty things and hard to get rid of. But, it can be done, and is well worth doing.