And the one constant through all that which you described is that "marriage" has been between a man and a woman.
And the one inconstant through all of that is that there is is no "traditional" sense of marriage, at all. The concept of "marriage" is not traditional in your sense at all.
In fact, every religion has their own version of marriage. And those who subscribe to no religion do too (and we appear to be in the majority). So which version do you submit the Australian Governnent should subscribe to? Yours? Forsaking all others?
Do you decry the secular constitution upon which our nation is based?