"A few months ago we didn't know if he'd be able to get legally married in Australia, so the fact that today he gets to have a husband is pretty incredible", she said.
Burns, who represented Australia at the world championships and Commonwealth Games as a 4x400m relay runner, will marry the love of his life at one minute after midnight on Tuesday at Carool near Tweed Heads.
Today is the first official day same-sex couples can Wednesday in Australia and some have wasted no time marrying on the stroke of midnight.
Kelly Mackenzie and Kirsty Albion Wednesday at Sandridge Estate on 6 January after successfully lodging a special Notice of Intended Marriage form, making theirs the first same-sex marriage in Tasmania.
"They have been a dream team", she told the ABC.
Around 60 guests counted down to midnight before the pair took their vows in the same place as their commitment ceremony five years earlier.
"It was just magical", Diana expressed to the Special Broadcasting Service.
Last month, the Australian parliament made same-sex marriage legal, following a national survey which returned 61 percent favorability among voters.
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"It was just magical", Diana told SBS News. "To be able to come back here and redo our vows and actually make it legal and finally have equality in Australia is incredible".
The waiting period expired on Tuesday with some couples wasting no time and marrying just minutes after midnight.
"Now we get to declare our love for each other again and have it recognised as a real union", Rebecca said.
Exemptions to the month-long waiting period have already been granted to couples who have Wednesday in Melbourne, Kalgoorlie and the north-west coast of Tasmania.
Antony McManus and Ron Van Houwelingen also Wednesday in the theatre where they met 30 years ago in Melbourne.
After several commitment ceremonies, Mr Van Houwelingen called it a "wedding planned for 30 years".
"It's been quite hectic trying to organise that in such a short amount of time".