Billie Jean King Reveals She Secretly Married Her Partner in 2018

Billie Jean King and her former doubles partner Ilana Kloss have been "life partners" for over four decades. They wore one another's rings and, despite friends like Elton John and John McEnroe not-so-subtly nudging them to tie the knot, never did. Or so everyone thought. It turns out one of the revelations in King's upcoming memoir All In is that the two were secretly wed in 2018 by former NYC Mayor David Dinkins in his apartment on Manhattan's Upper East Side.

In an interview withPeople, King shared that only three other people knew about the marriage: Dinkin's wife, an aide who was there to act as a witness, and the city hall employee who processed the marriage license.

"Nobody threw rice or smashed wedding cake in the other's face," King said. "One of the brides wore jeans and a lovely red scarf and the other had on a black shirt, a comfortable warm-up suit, and pearls -- ha! -- a personal touch of glamour that Ilana still teases me about."

What ultimately made King change her mind and get married, she explained, was that she wanted to show her true commitment to Kloss. "I felt very married to Ilana, whether I had a piece of paper or not," King said. "But I'd had a big problem with trusting and it meant a lot to show my trust in Ilana." Plus, as King writes in the book, "Years from now, I never want anyone to question how much I was committed to you."

The two kept the ceremony secret because it felt more special that way. "So much of our life has been public, keeping this private was something special we could hold on to, just for us," King quoted Kloss as having said. In fact, not even their closest friends knew the two were married until they read about it in advance copies of King's memoir.

King also shared her feelings on the concept of sexual fluidity. The tennis star was married to her college sweetheart Larry King for 22 years and was pushed out of the closet in 1981 when Marilyn Barnett a woman King had been involved with while still with Larry King, filed a palimony suit against the the tennis star.

Sexuality is "a continuum. You're finding your truth, and it doesn't have to stay the same," King explained. "I only liked guys when I was young. I didn't think about girls. And then all of a sudden I'm like, 'Oh my God, what's happening?' My truth was changing over time. It took me forever."

She's grateful that things have changed so much today and that kids now have more freedom to discover who they are. "The environment is different. If you want to say, 'I'm bi or I'm gay,' or whatever, they can find someone to say, 'Okay, that's good!' And it does evolve," King said. "We're all much more fluid in our sexuality than we realize. You can fall in love with somebody no matter what their sexuality is. It's much healthier today than it's ever been and hopefully, it will continue."

King's memoir, All In, hits shelves August 17.