Aww, hugs hugs . It's awful when we hit the end of our tether, good on you for seeking help .

It sounds really hard going for you all. It certainly sounds like you have tried lots of different strategies! Have you thought about what she is eating? Could what she is eating perhaps be causing her tantrums? The reason I ask is because my DS1 has ADHD and we found a HUGE difference in his behaviour when we cut out nasty additives and gluten from his diet. Some people notice that dairy causes their child to have behavioural issues. DS1 is much calmer and better behaved when he does not have those things. Even his teacher asked what we had done to him! I found the Fedup website (it's Australian based) really helpful in regards to info about food intolerances and behavioural issues.