Tanya Maree Quattrocchi was sent to trial on the charge of having sent emails to US pop singer Diana DeGarmo's friends, about the star's sex live.
Quattrocchi, 22 allegedly sent the emails to the star's family, contacts and work colleagues.
Police arrested Quattrocchi in April after they detained her PC and cell phone.
Ms Quattrocchi has pleaded not guilty to four counts of persecuting the American star between November last year and January.
Ms Quattrocchi was fanatical about the Tennessee singer Diana DeGarmo, 20, who played in the musical "Hairspray", said The Melbourne Magistrates' Court today, while they listened to her speaking.
DeGarmo said this woman called her almost every night, sent messages on MySpace account pretending to be her, including naughty emails.
"I have moved twice and she still finds me. I cannot have any private or professional life without her infiltrating it,'' Ms DeGarmo said in a statement.
"No matter what I do I cannot get away from her. She is still to this day stealing my online identity and harassing my friends, family and myself,'' she said.
Ms Quattrocchi supposedly sent emails stating the singer wanted to have sex with her brother, Ms Quattrocchi said the court.
Moreover, Quattrocchi claimed that the pop singer loved older men (her brother) and was a lesbian.
"Diana is a lesbian whore. I don't want her small hands touching me. I love guys and have sex with them,'' Ms Quattrocchi wrote to the singer's sister-in-law.
