The 31-year-old said depression was “nothing to be ashamed of” and told herself she needed to “grow some b******s, come forward and say something".
Speaking publicly for the first time about the severity of her condition, she told the Mail on Sunday that she has been unable to get out of bed, shower or eat at times due to her depression.
“You exist in this gloomy shell of a person. But you learn to deal with it,” she said.
Fifi, who calls herself the ‘unknown Geldof', said her depression was diagnosed during the time of her parent’s acrimonious divorce in 1996 when she was ordered by a court to see a therapist.
“I’m not going to link depression back to Peaches. It’s nothing to do with Peaches. I can’t, in all honesty, attribute my sadness about my sister’s death to depression,” she said.
Despite suffering from the illness for most of her life, Fifi said she has never told her father about her depression.
She also revealed she has never taken any medication for her condition, other than self-medicating on drugs and alcohol in her late teens.
“I’ve never taken antidepressants but who am I to say no one else should? People should try and treat their depression however they deem fit. Some people won’t want to get to the bottom of it."
She added: “Quite frankly, there is no bottom of it. Depression just exists.”
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