The 51-year-old actor kept the diagnosis a secret because of the shame he felt but has opened up about his diagnosis in a bid to support others going through the same thing.
He said, "I have to start in 2007. In June of that year, I was diagnosed HIV-positive."
The "Cinderella" star admits it has been tough "living with that shame in silence" for the last 14 years.
He added, "Having lived through the plague, my question was always, 'Why was I spared? Why am I living?' Well, I'm living so that I can tell the story. There's a whole generation that was here, and I stand on their shoulders. I can be who I am in this space, at this time, because of the legacy that they left for me."
"So it's time to put my big boy pants on and talk. I was the generation that was supposed to know better, and it happened anyway. It was 2007, the worst year of my life."
"I was on the precipice of obscurity for about a decade or so, but 2007 was the worst of it. By February, I had been diagnosed with Type 2 diabetes. By March, I signed bankruptcy papers. And by June, I was diagnosed HIV-positive. The shame of that time compounded with the shame that had already (accumulated) in my life silenced me, and I have lived with that shame in silence for 14 years."
And Billy insists he is "much more" than his diagnosis and, if anyone doesn't want to work with him in the future because of it, then he insists they are not "worthy" of him.
Speaking to The Hollywood Reporter magazine, he shared, "There's no more stigma - let's be done with that. It's time. I've been living it and being in the shame of it for long enough."
"And I'm sure this will follow me. I'm sure this is going to be the first thing everybody says, 'HIV-positive blah, blah, blah.' OK. Whatever. It's not the only thing I am."
"I'm so much more than that diagnosis. And if you don't want to work with me because of my status, you're not worthy of me."