Conor Oberst is to sue the woman who, in anonymous comments on a website, accused him of raping her. The Bright Eyes singer-songwriter filed a lawsuit in Manhattan federal court on 19 February, claiming the accusations were "despicable, false, outrageous and defamatory statements".

The woman accused Oberst of raping her backstage after a 2003 concert in a post on the comments section of the website xojane.com last year. "Conor took a lot from me including my virginity, my dignity, and self-esteem," she wrote. She said she had been introduced to Oberst by his brother – her English teacher at school – as a 16th birthday present.

Oberst's lawsuit says that the woman's allegations about his behaviour have damaged his career. He says he was accompanied by other witnesses at the time of the alleged assault. The lawsuit also says the woman claimed in her posts that she had not reported the assault at the time because of the reaction of her family and friends, posting it a decade later to help others.

The Associated Press news service contacted both the woman and Oberst's lawyer, but received no comment from either. TMZ reports that the lawsuit is asking for more than $1m in damages.

Oberst's publicist issued a statement reading: "The lawsuit filed today outlines [the accuser's] history of inventing stories and personalities online in order to gain attention. Although her false statements about Oberst have since been deleted from the locations where they were initially posted online, Oberst's suit alleges that her malicious lies spread across the internet and are archived by multiple blogs. Through his attorneys, Oberst requested that [the accuser] recant her false accusations, but she ignored the requests. Oberst has thus been forced to proceed with this libel suit in order to set the record straight and to clear his name.

"Oberst is seeking to promote the truth and repair the distress this has brought upon him and his family. Oberst intends to donate the proceeds of this suit to charities benefitting the victims of violence against women."

Oberst's next album Upside Down Mountain – his first solo album in six years – is to be released in May.

• This article was amended on 21 February 2014. The earlier version, relying on information in an Associated Press report, stated that Conor Oberst's lawsuit says he was also accused of punching the woman he is suing in the face. AP has since issued a correction saying that the woman did not accuse Oberst of punching her in the face.