Speaking for the first time about her ordeal, she told The Times police were suppressing the truth about the brutal attack because they fear it would damage the island's money spinning tourist industry.
The alleged victim, from London, said: "I would urge other young people to stay away. I would never feel safe going back to Koh Tao.
"I wouldn't tell people not to go to Thailand in general, it is one of my favourite countries. But it is a beautiful place with a dark side that blinds you."
Koh Tao is popular spot for British backpackers.
Following a series of unexplained backpacker deaths it has since become known as "death island".
This week 12 people were threatened with arrest after sharing details of the latest alleged attack on Facebook.
The London woman said she believes that her rum and coke was drugged in one of the bars along the beach.
She felt tired and left the bar and cannot remember anything since.
A male friend who ordered a drink at the same time suffered drowsiness and then blackout, she says.
Speaking from her home she said: "The next thing I remember is waking up. My shorts and underwear were off me.
"A Thai guy was standing over me. As I woke up he just smiled at me and then he took off. "He'd taken my phone, my money, my cards.
"I had really bad burn grazes on my knee which I've got scars from. I was in a lot of pain and I was covered in sand."
The Bangkok Post editorial took police to task for their alleged failings during the investigation into the woman's claims.
It said: "Why not treat the initial complaint seriously and without prejudice and refrain from persecuting netizens?
"The international community responds well to those who are willing to be responsible and can lose face gracefully when necessary.
"The police continue with their myopic conduct at the nation's peril and would be well advised to learn behaviour consistent with being on a world stage."
