Linda Nolan was duped by a hoaxer who pretended to be a victim of the Manchester terror attack.
The 58-year-old singer - who has incurable cancer - exchanged hundreds of Facebook messages and even spoke on the phone with a woman who claimed she had been injured in the explosion at Ariana Grande's concert in May.
However, Linda was horrified to discover that she had been duped.
She told the Sunday Mirror: "This is a vile human being. How sick can a person get?
"I think she's sick in the head - not only to jump on the bandwagon of the Manchester bombings when there are so many real victims, but to pick on somebody who has recently been re-diagnosed with cancer.
"I confided in her and we formed a strong bond. I wanted to help her and I thought we had a connection. But it turned out I had been fed a pack of lies. It's very hurtful and sinister.
"I am going through my own troubles trying to deal with my treatment so this is the last thing I need."
Linda was contacted on Facebook by someone called "Mia", who said her sister Emily was waiting to have surgery to have her leg amputated and she was Linda's biggest fan.
Linda then kept up a steady stream of communication to raise Emily's spirits but became suspicious when, after she arranged to visit, another person called "Luke" messaged to say Emily had died.
She said: "[At first] I was devastated. I just thought, "I have breast cancer, it's life threatening and all of that, but this poor 25-year-old girl has gone through all this".
"She must have panicked and thought I would turn up at the hospital when there was no one there.
"My family had started to become suspicious and they found out that the Facebook profiles I had been talking to were faked. When I found out it was all a hoax I just thought "why?""