He is survived by his partner of over 50 years, Peter de Waal.
The pair, from Sydney, met in 1966. They were foundation members of the Campaign Against Moral Persecution (CAMP), one of Australia's earliest and most influential gay and lesbian rights organisations. Together, they attended the first Mardi Gras in 1978, where marchers were met with police and some brutally beaten; saw the decriminalisation of homosexuality across every Australian state; and campaigned for same-sex marriage.
Bonsall-Boone remained an activist to the end, appearing with de Waal in a video published by The Equality Campaign in April as part an ongoing campaign to legalise same-sex marriage in Australia.
“In looking forward to dying, one of my sorrows is that I'm not taking Peter with me. I am going to miss him like crazy,” Bonsall-Boone said in the video.
“Marriage for Peter and me would be a great fulfillment of many years of association and love, and then I will know that we are officially a part of each other. Which we have been of course, for 50 years, but that's unofficially part of each other. To make it official would be just great.”
Kirk Marcolina, the media director at The Equality Campaign, spent a lot of time with Bonsall-Boone and de Waal in recent months.
He told BuzzFeed News they were “an old married couple in the best sense of the word”.
“They had a rapport with each other than you can't get unless you're with someone for that length of time,” he said. “They would finish each others sentences, complain about what it was like watching TV together.”
Marcolina also attended the most recent Sydney Gay and Lesbian Mardi Gras parade in March with de Waal and Bonsall-Boone.
“I had the honour of pushing Bon around in his wheelchair. Walking through the parade with those guys, I felt like I was escorting rockstars. The reaction from the community was just enormous,” he said.
“I feel very indebted [to him]. As a gay Australian I feel very lucky to have met him. It's a big loss for me personally, but a huge loss for the community as well.”
“They are – together – the most phenomenal symbol of why equality matters,” Tiernan Brady, director of The Equality Campaign, told BuzzFeed News. “This is a couple who have been together for 50 years. That's love, and commitment, and more than most of us will ever achieve.
“It's the saddest of reminders that time isn't a luxury, and life is short.”
For their 50 year anniversary, in October last year, de Waal organised for their “honorary grandchildren” to present them with wedding rings in recognition of how much Bonsall-Boone wanted to marry.
“I'd love to be able to move my wedding ring from my right hand to my left hand, and then I'd be able to call him my husband… that would be wonderful, wouldn't it?” Bonsall-Boone said in the video.
“We've been second class citizens for all of the 50 years we've been together,” said de Waal. “It would be absolutely wonderful if we could say one day, we are equal.”