i would wait until the end of your cycle to get a proper reading on what is happening.
try to add the salt to soups or food instead of water for the time being, at least those will have more of a nourishing effect rather than just cleansing.
if you add enough to your foods, plain water will start to taste good again.
i doubt it is a fluoride reaction. if the salt is causing you loose stools or causing too much urination then you could possibly be encouraging some dehydration, but wait till the end of your cycle to figure it out.
my suspicion is that you will go through a period of time feeling worse and then have a significant health improvement. be sure to support all of your other organs and adrenals while this is happening.
i went through something vaguely similar with lemons. i couldn't stop drinking lemonade/ lemon juice, it just tasted too good for me to stop. it was causing some hair loss, but i kept with it and eventually the hair loss subsided and then my hair grew in much better than it had been for a very long time. sometimes the body just has its own wisdom and timetable, and usually strong cravings or tastes are a very good measure of this type of thing.