The public figure began her career as a classical singer before crossing over as a pop singer.
She came out as bisexual in May 2018 after being nominated for a LGBTI award.
It hasn't been the easiest road for the couple - Marvelly wrote a Herald column in February 2019 sharing her disappointment at the loss of Auckland's Pride Parade.
The parade's existence had "loudly declared that the rainbow communities had the support of business, Government, and organisations of all shapes and sizes", she wrote.
"It told the prejudiced and narrow-minded that it was them, and not us, who should be ashamed."
Marvelly wrote that this message was as relevant as ever because she had a few weeks earlier been standing hand-in-hand with her now wife Gerrard at a traffic light.
When Marvelly kissed her partner, a young woman behind them "shrieked, 'Oh my God, lesbians!'"
Marvelly said she and her partner froze, stunned, as the woman "continued her tirade".
"'Maybe we should take them home with us ... A blonde and a brunette ... hot!' she said suggestively to her male partner, dissolving into laughter."
The incident highlighted society still had a long way to go, Marvelly said at the time.
"If we'd been a man and a woman, that very tame kiss would've been entirely unremarkable," Marvelly wrote.
