Duffy has shared a harrowing account of being raped, drugged and held captive, saying she was at "high risk of suicide" following the ordeal.
The 35-year-old Welsh singer , whose full name is Aimee Anne Duffy, said she was telling her "dark story" to help "others who have suffered the same".
She first revealed she was drugged and raped by an unnamed attacker in February , and revealed more details of what happened to her via a lengthy post on her verified Instagram page.
She wrote: "I hope it comforts you to feel less ashamed if you feel alone.
"It was my birthday, I was drugged at a restaurant, I was drugged then for four weeks and travelled to a foreign country.
"I can't remember getting on the plane and came round in the back of a travelling vehicle.
"I was put into a hotel room and the perpetrator returned and raped me.
"I remember the pain and trying to stay conscious in the room after it happened.
"I was stuck with him for another day, he didn't look at me, I was to walk behind him, I was somewhat conscious and withdrawn.
"I could have been disposed of by him."
She said she does not know how she had "the strength to endure those days", and claimed the perpetrator made "veiled confessions of wanting to kill me".
Duffy said "we are living in a hurting world".
She added: "I am no longer ashamed that something deeply hurt me, anymore. I believe that if you speak from the heart within you, the heart within others will answer.
"As dark as my story is, I do speak from my heart, for my life, and for the life of others, whom have suffered the same."
Duffy said that she escaped by "fleeing", but did not provide an account of how she got away, adding she "cannot remember getting home".
She said that she initially feared going to the police, but eventually told a female officer what happened after someone threatened to "out her story".
Duffy added that she was at "high risk of suicide" following the ordeal and has spent "almost 10 years completely alone".
But she said she now feels she can "leave this decade behind" and is "free", thanking her psychologist for helping her through the trauma.
She said she hopes to release "a body of work some day", but added: "I very much doubt I will ever be the person people once knew."
When Duffy broke her silence about the incident she said many of her fans would "wonder what happened to me, where did I disappear to and why".
Duffy had a UK number one album with her release Rockferry in 2008.
The following year she won three BRIT Awards (British Breakthrough, Best Female Solo and Best British Album) and a Grammy (Best Pop Vocal Album).
Her last album, Endlessly, came out in 2010 and was judged to be a commercial failure.
Anyone feeling emotionally distressed or suicidal can call Samaritans for help on 116 123 or email email@example.com in the UK. In the US, call the Samaritans branch in your area or 1 (800) 273-TALK.