I suggest you contact your Domestic/Family Violence service. They are in the local Yellow Pages and it is a freecall number. To me (from what you have posted), it sounds like he is emotionally and verbally abusive so you need some support. They may be able to help with short-term accommodation if you have nowhere else to go.

Regarding finances, I am assuming you are an Australian citizen or permanent resident. Contact Centrelink and ask what support you can receive.

From the sound of it, you have pretty much made your decision. I believe it is better to deal with the situation early, otherwise you run the risk that your children will start to display the same behaviour and that will bring a whole NEW set of problems.

Good luck