Charlotte MacInnes is suing the Hollywood star over social media posts claiming she complained about feeling uncomfortable after bathing with Amanda Ghost, Wilson's co-producer on musical film The Deb.
MacInnes also alleges the posts - which could be seen by Wilson's 11 million followers for 24 hours - suggested she had withdrawn the complaint in exchange for plum acting and music opportunities.
MacInnes was thrilled to be cast and looked forward to working with Wilson, her boyfriend Carlo Boumouglbay wrote in an affidavit tendered to the Federal Court on Wednesday.
But she felt isolated after she was asked to leave an apartment where she stayed with Ms Ghost and others following the airing of Wilson's allegations.
"She also started to be suspicious and thought Rebel might be spreading misinformation about her and spinning some type of story," Mr Boumouglbay wrote.
MacInnes was very upset Wilson made a false claim about her after feeling on a number of occasions the older actor was dismissive and disrespectful to her on set, he said.
Wilson's subsequent social media posts suggesting MacInnes retracted the claim in return for a record deal and a leading role left the young actor in tears, Mr Boumouglbay attested.
"She thought Rebel was monitoring her at all times," he wrote in his sworn statement.
"She was fearful for her safety and felt vulnerable."
Wilson's conduct "deeply wounded" the young actor and has left her constantly on edge, Mr Boumouglbay said.
MacInnes claims her professional reputation was ruined by suggestions she is untrustworthy and prioritised her own career over those of the 300 cast and crew who worked on The Deb.
But Wilson's barrister Dauid Sibtain SC argued MacInnes hadn't suffered any harm to her career at all since his client's first social media post in September 2024.
MacInnes signed a record deal with Atlantic Records in late 2025, her manager Shoshanna Stone told the court.
The deal provided for two EPs and included an advance worth $US110,000 ($A154,000), she said.
Ms Stone's high-profile clients include Britney Spears, Shakira, Boy George and Alicia Keys.
She told the court she signed MacInnes to her roster after being informed of the young actor's talent by her friend, Ms Ghost.
The up-and-coming performer's second single is due to be released on Thursday.
Her manager rejected suggestions it had been timed to coincide with the court battle.
The Deb's co-writer, Hannah Reilly, hailed MacInnes as a "bright star in the making" who had been irrevocably "hardened" by the social media posts.
MacInnes confided they had taken away some of her innocence and trust in the world, Ms Reilly wrote in an affidavit.
The young actor said she was experiencing vivid nightmares, panic attacks and stopped eating for days at a time.
"She has expressed to me that it has been an all-consuming nightmarish force in her life," Ms Reilly wrote.
She thought Wilson's subsequent social media posts suggested MacInnes was a liar who traded sexual favours to secure a role and a record deal.
Wilson denies the posts are defamatory and maintains the young actor made the complaint before retracting it in order to ensure her future as a performer by appeasing Ms Ghost.
The Deb was released in Australia earlier in April after legal issues prevented its widespread release following its 2024 film festival premiere.