Kate Spade's best friend is speaking out following the designer's suicide in June.
In an interview with Good Morning America on Thursday, Elyce Arons opened up about her friend -- whom she called Katy -- and her legacy.
"I have a really hard time calling her Kate because that came about through the business, but I had known her for so much longer than that," Arons said of Spade, whom she met at the University of Kansas.
"It was tough because she didn't always say it," Arons revealed of her late friend's battle with depression. "She'd be sad and then one minute later she'd make a joke."
Arons, who was also Spade's longtime business partner, said that her friend was generally happy. "We talked every day and most of the time she was very happy," she said. "But I don't know if anyone can understand the depths of depression of another person."
As for remaining questions, Arons just has one -- "Why?"
"I have thought and thought and thought about it, but I think it was probably one moment of despair, of deep sadness that she felt while she was alone," Arons said. "I can't answer what that was."
Back in 2016, Arons and Spade -- along with the designer's husband, Andy Spade -- co-founded Frances Valentine, an accessories line. Spade worked up until her death and always wanted to innovate.
"Katy had this need to create, and this was it," Arons said of the line.
In honor of Spade -- and the people she inspired -- the brand will live on, thanks to Arons and the team of 10 behind the line.
"We've had ... a lot of people write in and and talk about how she had changed their lives," Arons revealed, before adding that many say, "'Please keep going and keep her designs alive.'"
"That's what we're going to do," she said. "We miss her every day. Her spirit's here."
With the collection readying to launch during New York Fashion Week, Arons hypothesized that Spade would advise her to "take a vacation."
"I think she would be thrilled," Arons said of the collection's completion. "I think she would be really happy."
As a friend, Arons said she thinks if Spade were still here she would tell her, "'I'm OK,' she'd say. 'I'm OK, don't worry about me.'"
Here's more on Spade:
Kate Spade's Husband Andy Remembers Late Designer With Heartfelt Tribute
David Spade Recalls How Kate Spade Always Made His Past Girlfriends Feel Special
Kate Spade's Dad Dies One Day Ahead of Her Funeral