Thank you everyone. Charlie's urine is almost totally back to normal now (I never thought I'd be thankful to have a cat who peed in the sink!). I'm still sad to think of how much unneccessary stuff I put her through, but hopefully my good intentions will outweigh her trauma in the end. Last night she played with the "Da Bird" toy when it was out, even leaping to catch it a couple of times, so I think she's feeling pretty good.

Smokey, I googled the use of glucosamine and chondroitin in FIC cats after I saw your post and found a lot of good info that says it might help, so I'll be buying her some "hip action" treats tomorrow. Thanks for the tip!! Any excuse to give them more treats is a good one!