Kate Spade's Lasting Legacy: Inside the Designer's Trailblazing Career and Private Pain

After Kate Spade’s tragic death on June 5, her family, friends and fans are honoring her legacy while trying to understand the pain that led to the iconic designer’s suicide at the age of 55.

“We knew Kate had her problems and demons,” one friend tells PEOPLE in this week’s cover story. “But no one would have ever expected her to do this.”

The fashion industry vet, who sold her eponymous company in 2006, then returned to the design spotlight two years ago with her accessories line Frances Valentine, was born Katherine Brosnahan on December 24, 1962, in Kansas City, Missouri. After graduating from Arizona State University, she moved to N.Y.C. in 1986 to work as a temporary assistant on a Mademoiselle magazine photo shoot.

She rose up the masthead, eventually landing the title of accessories editor, but not content just to feature others’ designs, Kate left the magazine in 1993 to launch Kate Spade New York from her home alongside then-boyfriend Andy Spade, combining her first name with his last a year before they wed. The initial launch of her signature boxy handbags (with the labels stitched on the outside, a last-minute decision that caught buyers’ eyes) revolutionized the accessories industry in the ’90s.

RELATED PHOTOS: Kate Spade’s Celebrity Fans and Most Memorable Pop Culture Moments

Kate’s bags “helped shape the aesthetic moment of the time — simple but meaningful and functional,” says CFDA president Steven Kolb, who adds that the designer, “changed the way women—and the world— viewed American fashion through her signature, playful lens on design.”

Adds former CFDA executive director Fern Mallis, “She was as adorable as her accessories were. She and Andy were very much in the front lane of the fashion universe.”

RELATED: Our Decision to Put the National Suicide Prevention Lifeline Number on This Week’s PEOPLE Cover

Three years after it launched, Kate Spade New York was a $5 million business, with her original collection’s designs still among the brand’s bestsellers. (Since her death, sales of original Kate Spade bags have skyrocketed on resale sites including thredUP and Poshmark.) “If you can’t keep wearing the things in our line, then we feel we made a mistake,” Spade told PEOPLE in 1996, as her label achieved tremendous success.

In 2006, Kate and Andy sold their company to Neiman Marcus, banking $92.6 million for what they had built. Their daughter Frances Beatrix, called Bea, had just been born, and Kate stepped back from the industry to focus on being a mom – a break that would last for a decade.

“It was so natural for me to get involved in my daughter’s school, her playdates and baking,” Kate told PEOPLE during an intimate sit-down interview at her Park Avenue home in 2016.

For PEOPLE’s tribute to two icons: Talent & Tragedy, pick up this week’s issue, on newsstands Friday.

Spade was by all accounts a dedicated mom and very much the effervescent personality she lent to her namesake brand, which is why friends and fans alike were shocked when a housekeeper arrived June 5 to find Kate alone and unresponsive in her bedroom. The New York City’s medical examiner’s office officially declared the designer’s a suicide.

Her husband, Andy, 56, revealed on the day of her death that Kate had been in treatment for depression and anxiety. He also confirmed the couple’s separation, noting that he had moved out 10 months earlier to an apartment several blocks away, where Bea, 13, spent half her time.

“We were in touch with [Kate] the night before and she sounded happy,” Andy said. “There was no indication and no warning that she would do this. It was a complete shock, and it clearly wasn’t her.”

If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text “help” to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.

For his part, Andy, who co-founded pajamas and loungewear brand Sleepy Jones in 2013, maintained that the split was temporary and amicable, adding that the trio still traveled together as a family.

“We were best friends trying to work through our problems,” he said.

Kate’s 89-year-old father told Frank Brosnahan told The Kansas City Star he was gratified by the attention Kate’s death brought to mental illness and suicide: “Any talk that . . . helps somebody else, Katy would have liked that.”

While funeral arrangements have not been confirmed yet, Brosnahan hopes to bring his daughter back to her home state of Kansas to be buried beside her mother.

For more on the life, legacy and loss of Kate Spade, pick up the new issue of PEOPLE, on newsstands Friday.