Thats really sad bro.
Still, it is always better to talk to her before you come to any conclusion. If  that was fake marraige or sth like that and if you think you can consider that, it would be good. Otherwise, First try to get your money back and then you can do whatever you want, ruin her life or leave her. If she doesnot cooperate and reply you with random answer, as JAI mentioned above, notify Austrailian government and get them (both) back to the country. Spend another sum of money and get the job done (whatever you think is good job).

Hope everything turns good after you talk to her.