Sorry to hear your problem LittleBay. Before you throw in the towel, please consider the following.
I'm in CT right on the coast where many homes got clobbered by Sandy last year, and the storm in 2011 which I can't remember the name of. I also own a civil engineering/land survey company, one of our services is producing FEMA flood certificates which are used by insurance companies to determine premiums. Have you had a flood certificate done recently? It is possible (I stress possible) that the premium will be reduced depending on the specifics of your homes construction in relation to the flood hazard zone where you live.
In the last two years we have seen extreme examples where premiums go from $500/year to $4,000/month. Yes, $4,000/month, obviously those people had to pay off the mortgage or leave. We have also seen a few where, absent a flood certificate, the premiums had been determined by putting the house in the highest risk category. When a flood certificate was subsequently produced and the house was not in the highest risk group, the premium was reduced. Your $6,000 premium sounds a pretty high to me unless the house is right a lake level, perhaps they get a lot of ice damage claims? The feedback we get from clients is that most premiums around here are in the $1,500-$2,500/year range, this for relatively high value structures.
Best of luck to you.