Same sex relationships, including marriage, are gaining legal and public acceptance
Many countries have established laws to enable same sex couple to marry with all the same benefits and responsibilities as heterosexual married couples.
Extract from Wikipedia ( September 2017)
In the late 20th century, rites of marriage for same-sex couples without legal recognition became increasingly common. The first law providing for marriage of people of the same sex in modern times was enacted in 2001 in the Netherlands.
As of 1 September 2017, same-sex marriage is legally recognized (nationwide or in some parts) in the following countries: Argentina, Belgium, Brazil, Canada, Colombia, Denmark, Finland, France, Iceland, Ireland, Luxembourg, Malta, Mexico,[nb 1] the Netherlands,[nb 2] New Zealand,[nb 3] Norway, Portugal, South Africa, Spain, Sweden, the United Kingdom,[nb 4] the United States[nb 5] and Uruguay. The law in Germany is not yet in force. Same-sex marriage is likely to soon become legal in Taiwan, after a constitutional court ruling in May 2017. Polls show rising support for legally recognizing same-sex marriage in the Americas, Australia and most of Europe. However, as of 2017, South Africa is the only African country where same-sex marriage is recognized. Taiwan would become the first country in Asia to legalize same-sex marriage if the Civil Code is amended. Israel and Armenia recognise same-sex marriages performed outside the country for some purposes.
Other countries have enacted laws giving same sex couples same benefits and responsibilities as heterosexual married couples, but call such relationships 'civil unions' rather than 'marriage'.
Australia is one of the countries that has not yet enacted legislation to grant same sex couples the right to marry.
However there are various Australian jurisdictions that have established relationship registers, which granted those registered the ability to publicly notify their relationship. Such recognition can be grounds to verify the relationship's nature and duration should this be needed, usually for matters related to sickness or death of one of the parties in the relationship.