Up to you if you want to finalise the divorce. Like sammy and Rod mentioned - if you are thinking of marrying again, you will not be able to.
If either of you die at the moment, you will pass all your inheritance to the other. Might be worth just finalising it with a formal divorce. Costs like $900.
I'm a family lawyer. If you want some more advice or even just a chat on your situation, you can book at time that suits you at: Hayder Shkara, Sydney Lawyer: Book Online or call my office. I can give you some advice as to what you should do.