A British man whose partner died on their Australian honeymoon says he is living through a “nightmare” after authorities refused to recognize he was ever married in the first place.

As a result, all the decisions around his spouse’s death have had to be made by family members thousands of kilometers away, a situation slammed as “horrific” by critics who have urged the government to intervene.

Further compounding the heartache surrounding the death of David Bulmer-Rizzi, who suffered a fatal accident last Saturday in Adelaide, is the realization that if he’d died in Melbourne or Sydney, the fact he was gay would barely have raised an eyebrow. But in South Australia it was enough to ensure his husband Marco Bulmer-Rizzi was shut out of almost every decision following his death.

David, 32, married his partner of five years, in London in June last year followed by a full ceremony in front of family and friends on the idyllic Greek island of Santorini. Same-sex marriage was legalized across much of the UK in 2014.

“David was passionate about human rights, he was generous, loved life and loved to party with people,” Marco, 38, told news.com.au. “In many ways, he was very Australian; maybe he should have moved to this country.”

The couple began their Australian honeymoon in late December with Facebook posts detailing their travels around the country. But tragedy struck last weekend when David fell down the stairs in the Adelaide house they were staying in.

“I went to bed and David was to follow me shortly. He was just reading his Kindle. I woke up 45 minutes later and heard this awful noise and I turned on the light and he was lying at the bottom of the stairs in a bloodbath,” Marco told Buzzfeed UK. He suspects it was because he was unfamiliar with the house and it was dark.

An unconscious David was placed in an induced coma but the damage to his head was too severe and he succumbed to his injuries.

However, the pain was only about to begin. While same-sex marriage is illegal within Australia, all the eastern states recognize same-sex marriages performed overseas and allow partners to act as next-of-kin. South Australia does not.

 “Literally within an hour, I had no choice but to deny that we ever married,” Marco told news.com.au. “It made me feel humiliated and lonely. I felt like it was 20 years ago when you couldn’t come out for fear of being treated differently.

“I asked if I could at least leave that part [of the death certificate] blank but they said the drop down box wouldn’t allow it.

 “The computer said no. There was no room for humanity and I think that’s the shocking part. It’s a complete nightmare what’s happened.”

Every decision Marco wanted to make, from whether David should be cremated to what coffin to use, had to be rubber-stamped by his late husband’s father, Nigel Bulmer, back in the UK. While Mr Bulmer backed his son-in-law and explained they were married, the authorities refused to budge.

Marco’s treatment has riled lesbian, gay, bisexual, transgender and intersex (LGBTI) advocates, who say his case shows why marriage equality is needed now.

South Australian Greens senator and marriage equality spokesman Robert Simms said he would raise the widow’s plight in Parliament. He has also called on Foreign Minister Julie Bishop to provide him with support.

“He has been treated in a degrading and dehumanizing way and I’m horrified about his experience,” Mr Simms said.

“It’s very disappointing and particularly when you consider South Australia led the way when it came to the decriminalization of homosexuality but now the state Labor government is asleep at the wheel.”

Independent Sydney MP Alex Greenwich, who wed his male partner Victor in Argentina, was one of the key backers of a 2014 change in NSW laws, which saw same-sex marriages performed abroad recognized within the state.

“While the federal government continues to delay marriage equality, couples are not waiting; couples are going overseas and getting married and coming to Australia,” he said.

“This is a person who is grieving with the loss of their partner and all of this is completely unnecessary.”

Australian Marriage Equality South Australian convener Harley Schumann said:

“Most South Australians would find it appalling that our law has failed to recognize the love and commitment in David and Marco’s relationship. It’s time for us to join Tasmania, Victoria, NSW and Queensland in recognizing overseas same-sex marriages.”

South Australian Premier Jay Weatherill said the government had begun to remove laws from the statue books that were examples of “senseless discrimination”.

“We will introduce a further raft of legislation to the Parliament this year that will grapple with the more complex issues such as this,” he said.

For Marco, the support he’s received since David’s death just days ago has been overwhelming.

“Australians are amazing people and that’s why we chose to come here,” he said.

Asked if he had a message for the state and federal government, he told news.com.au: “I appreciate Australia has to go through its own process but I’m just asking to be treated with dignity and for some compassion. My entire life was denied in front of me because being married to David was my life.”

David’s organs have now been donated to a number of people, one who was waiting for about four years for a transplant.

“Three Australian families have been given the gift of life and that was probably the best moment from all of this,” Marco said.

“David’s life will continue and it provides relief for otherwise unbearable grief.”

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