"Spade's older sister, Reta Saffo, suspects the designer may have suffered from bipolar disorder Saffo tells CBS This Morning she ".Tried numerous times to get her help".
He said her death was a "complete shock".
Though their family tried to get Kate into treatment, it never happened because "she was definitely anxious about what people would say if they found out".
"I, personally, I don't know about Andy - took off a good nine years raising my daughter and absolutely adored every moment of it", Spade said last April.
Mr Spade said in the statement that his wife had been working closely with doctors to treat the "disease which takes far too many lives".
"We worked together at a clothing store, and I was on the women's side". Born in Kansas City, Missouri, Spade leaves behind her husband of 24 years, Andy, and a daughter, Frances Beatrix Spade.
Spade, who married Kate Spade in 1994, also said in the statement that the couple had been living separately for the last 10 months.
"Kate designed with great charm and humour, and built a global empire that reflected exactly who she was and how she lived".
Two relatives of the designer whose comments are not being questioned are those of her brother-in-law, comedian David Spade, and niece, actress Rachel Brosnahan. "Sometimes you simply can not SAVE people from themselves! We loved each other very much and simply needed a break", he said, adding that he was "appalled" that the contents of an alleged suicide note were shared with the media. "Please!' I know she perhaps had a plan, but she insisted she did not", Saffo added.
"We were freaked out/saddened, but she kept watching it and watching it over and over", wrote Saffo. "My daughter and I are devastated by her loss, and can't even begin to fathom life without her", he writes.