I'm glad you updated, I was starting to wonder about the cast and if there was an infection--I know that you probably had to seek out a vet who would cast rather than do surgery to save money and unfortunately, while it is indeed WAY less money when it does work, it does often have these results. The good news though, like the others have said---cat's with 3 legs do GREAT, you probably won't even notice. My folks had my cousins cat (they took him when Jason had kids--buddy did NOT like kids and would seek them out and attack them!) Anyway, he was the toughest piece of cat ever, he had his tail and back leg amputated when he was 2--he got caught in a fan belt. That cat could hunt and kill racoons...on 3 legs without a tail. he was WILD.
Anyway, I totally sympathized with you--when I posted the other "what ifs" I wasn't doubting you--I was offering possible reasons I wouldn't have done what you did, but most probably, if I thought the dog was in IMMEDIATE danger like you did, I'd have done the same damn thing so

Please keep us updated on your kitty, I'm guessing she'll start eating no problem once that infection is dealt with and then you can actually begin to heal from this--it's hard to move on when your kitty isn't. I'm glad you talked the ex out of sueing, you're obviously a tough mama.