Hi Ferbs and welcome to the forums.
Ok so I have to say it... What. An. Asshat! That feels better. Your boss is not only a bully but also completely out of line.
I wonder if you have considered calling the fair work ombudsman to ask for advice? I would be checking their website for sure.
Ok so you are leaving and it might seem a little pointless to create more stress for yourself. But along with making you utterly miserable she has threatened to poison your chances of other employment by giving bad references. Stuff that. And stuff her.
Why shouldnt you be allowed a fresh start and a working environment where you feel safe? Funnily enough it is something the law is meant to protect.
I quit a job as I was very unwell and like you I was not well enough to work out the remaining time. I was fortunate to have a supervisor who understood I was unwell and stood up for me to management and made it happen. You don't have this luxury so it is important you have support.
Is there anyone else in the organisation you can ask for a reference? Having a reference (even a colleague) is better than none I thought. Plus if a potential employer does contact the workplace and run into this yoad of a boss hopefully they will receive two very different references.
One thing I do know is that you are within your rights to ask for another person to attend all meetings with you. So when you meet with your boss to give the medical notice please make sure you have someone you trust with you. It also means you have a witness to any bullying behaviour.
On that note make sure you are documenting all of her threats and bullying. This is your future employment and she is in the wrong with no right to stop you from seeking a safe working environment.
I hope you keep writing and reaching out. Not long to go till you escape and start fresh. Please take good care of yourself.