Harrison is being pursued by Seven West for legal costs after she agreed to a gag order, banning her from speaking publicly about her relationship with Worner or releasing confidential company documents.
Harrison made the revelation on Twitter that she would no longer fight the company and its gagging order.
"I have made a realistic assessment of the court case and am choosing not to run it," she tweeted.
"I've asked my legal team not to represent me."
In March, Harrison hired prominent barrister Julian Burnside QC in her continuing legal battle against Channel Seven.
Harrison claimed the media company contravened the Fair Work Act and breached her employment contract. She has also filed an adverse action claim under the Fair Work Act.
At the time, Harrison's lawyers said Seven contravened the Fair Work Act because it reformed her role with the company "to her prejudice" and "injured her in her employment" after her 18-month affair with Worner ended in the middle of 2014.
The 39-year-old claimed Seven took adverse action against her after her relationship with Worner ended by investigating her alleged misuse of a corporate credit card.
Harrison also alleged Warner had used illicit drugs and approved a bonus payment to her during their relationship while she was employed by Seven.
In April, Seven announced the appointment of Katie McGrath as group executive of human resources
Seven’s former HR head Melanie Allibon left the company in December 2016, shortly after the two-year affair between Harrison and Worner was made public.
Allibon played a prominent role in the efforts to negotiate Harrison out of the organisation after executive chairman Kerry Stokes was told about Harrison’s affair with Worner.
Harrison is due to address the New South Wales Supreme Court by telephone today on the issue of costs, but company lawyers have been allowed to read her statement first to make sure that it does not contain "scandalous material".
Former Channel Seven employee leaks sensitive information
Film company pleads guilty to Star Wars safety blunder
Former HR boss charged over six-figure fraud
The former Seven West Media executive media assistant Amber Harrison has abandoned her legal battle with her former employer.