Upvote:2
The documentation about funds is used as proof of:
That you can maintain yourself during the visit (12,000 AUD are 8,664 €, definitely way more than enough to sustain yourself for a month, even if you had to paid hotels and air tickets from it).
That these funds are yours (they come from your salary/other incomes, instead of being money someone lends you to "sponsor" your visa)
That you have ties to your country of origin (for example a job) that will ensure that you are not enticed to stay in the Schengen area beyond the limits of the visa.
In addition to bank statements, your work contract in Australia and a couple of pay slips would help the IO to dismiss any doubts he could have about the above points. Explaining that you are travelling with your boyfriend and including the same documentation from him will not hurt, even if it is not required.