Celebrity event planner Marcy Blum just pulled off one of her most memorable weddings yet — her own!

Blum and longtime love Destin Coleman tied the knot on Saturday on St.

Barths. In a fun twist, their guests had no idea that a wedding was about to unfold.

The couple and 20 of their closest friends gathered on the Caribbean island for a weekend-long celebration in honor of Blum’s birthday.

After kicking off the festivities on Friday night at Le Carl Gustaf followed by some lively dancing on tables at La Petite Plage Saint-Barth, the group gathered again on Saturday at a villa owned by two of Blum’s clients for what turned out to be her surprise nuptials.

She and Coleman exchanged personal, handwritten vows as they stood in front of a stunning floral arrangement from Liberty St. Barths. The bride wore a custom ivory silk satin dress made for her by Patricia Voto of One/Of, and carried a small bouquet.

“I’ve cried at many weddings over the years but Destin’s vows were so beautiful, I was practically incoherent,” Blum tells PEOPLE exclusively.

In a touching gesture, Darren Olarsch from On the Move surprised Blum and Coleman by flying in live singers for the occasion instead of orchestrating a playlist. Photographer Allan Zepeda — with whom Blum has worked on numerous events including NBA star Kevin Love’s wedding to model Kate Bock — was not only a guest but also photographed Blum’s vows.

The couple and their guests then celebrated the joyous occasion with sunset cocktails and a quiet dinner at Eden Rock. For the festivities, the couple had very special music in mind, and Darren from On the Move surprised the pair by flying in live singers instead of orchestrating a playlist.

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Blum and Coleman — who have been together for 22 years — chose to have a surprise wedding due to the sheer size of their potential guest list. Between Blum’s clients and business associates and the couple’s many friends, the list would have surpassed 500 people.

An expert in the wedding and event planning business, Blum has been the mastermind behind countless A-list celebrity weddings.

Instead of throwing a massive bash, they hosted a small, intimate event with their closest circle of loved ones, some of whom they’ve known for more than 50 years. The combination of their long-time friends from the over years and their recent friends was a beautiful, eclectic bunch from various facets of life all coming together to celebrate.

The wedding weekend wrapped up on Sunday with a day party at Nikki Beach, which included dinner bites on the wraparound balcony at the Howard Hughes suite at the Eden Rock.

On Monday, Blum’s actual birthday, the staff at Cheval Blanc — where the planner and Coleman were staying in a suite on La Flamands Beach — surprised the newlyweds with celebratory balloons and champagne.

For more than 35 years, Blum has been one of the most sought-after celebrity event planners. She has worked with VIP clients including LeBron James, Nate Berkus and Jeremiah Brent, and Bill Gates’ daughter Jennifer Gates and Nayel Nassar.