Furnish's husband, music legend Elton John, will be on tour in Europe when the Toronto native takes part in the parade on June 28. The couple's young sons, four-year-old Zachary and two-year-old Elijah, also won't make the trip.
But the producer and philanthropist said his parents and brothers are excited to have him home, and John will be cheering him on from across the Atlantic.
"Any opportunity with Elton to promote the message and to fly the flag, he's always very positive and supportive," Furnish said in a phone interview from London.
Furnish will also be guest of honour at a private reception in support of Pride Toronto and the Elton John AIDS Foundation, which he chairs.
His role with the Pride parade was announced on Tuesday, just days after what is being hailed as a landmark moment for the LGBT community: Bruce Jenner's declaration in an ABC News interview that he identifies as a woman.
Furnish said he hasn't yet seen the interview, but called the former Olympic champion "incredibly brave."
"I think people should be supporting him in his decision and in his choice," Furnish said.
"I think people should always feel 100 per cent free and unencumbered to be true to themselves, and to have the courage and the support to speak up and move forward with their lives."
Furnish's husband has made headlines of his own in recent months. In March, John called for a boycott of Italian label Dolce and Gabbana following controversial remarks by the brand's designers about gay adoptions. They also referred to babies born via in vitro fertilization as "synthetic."
Domenico Dolce and Stefano Gabbana have since slightly backtracked on their comments, with Dolce telling CNN his views on IVF were private. But Furnish, whose sons were born via surrogate, said his stance remains unchanged.
"Obviously it's something they don't feel comfortable with, and I respect that," he said.
"But to call all children born of IVF synthetic ... I think is really misinformed and very damaging and potentially very hurtful.
"We have decisions and choices and places in life where we can act and respond accordingly, and I wouldn't feel comfortable spending money in their shop or wearing their clothing anymore."
Furnish said while he is excited to celebrate at Pride, it's critical not to become complacent.
He is particularly concerned about raising awareness about HIV-AIDS. He said young gay men account for 64 per cent of new HIV infections, even though they're estimated to represent just four per cent of the Canadian population.
And while LGBT issues have loomed large in the headlines in the past year — with professional athletes publicly declaring their sexuality and greater visibility of trans individuals — Furnish said it's still important to recognize the work is far from over.
"There are so many other countries in the world where it's illegal to be gay — 81 in total," Furnish said.
"Parts of the world seem to be going backwards rather than forward, where people aren't as lucky and as blessed and as supported as we are, and I think we send a very strong message to the rest of the world. We don't just live in little pockets and in little isolated communities anymore.
"I think where we have a good story to tell we should be shouting it from the rooftops and providing inspiration and hope and support to people that don't have the same benefits as we do."
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