Rebekah Vardy and her agent "monitored and stalked me", Coleen Rooney told the High Court, as she accused both women of sending "evil" messages about her.
Rooney, the wife of former England player Wayne Rooney, was giving evidence in the second week of the "Wagatha Christie" libel trial after her 2019 social media post that accused Vardy, the wife of Leicester striker Jamie Vardy, of leaking stories to the tabloid press.
Rooney, 36, told the court that Vardy, 40, and her agent, Caroline Watt, sent "evil and uncalled for" messages about her when they were discussing her private Instagram posts.
The court has previously heard that Vardy and Watt, who is no longer involved in the legal proceedings due to ill health, exchanged lengthy Whatsapp messages in which Rooney was called a "nasty b****".
"There is no need to talk about me or my Instagram, especially with Caroline Watt," Rooney told the court.
"I don't know what Caroline Watt looks like – I've never spoken to her, never met her."
She continued: "I'm totally the opposite of what they described. I'm not a bad person, the words they used are just totally untrue and there's no need for it.
"I've done nothing to them for them to talk about and monitor and stalk me."
The court heard that Rooney concocted her plan to carry out a sting operation when she tried to remove Vardy as a follower from her private Instagram account, but her fellow WAG noticed and texted her to ask why.
Rooney said the pair were "not good friends" and that if someone had unfollowed her she would "probably just forget about it and not message" the person, adding: "I wouldn't have been that bothered really".
"I felt it was suspicious. Obviously, I had suspicions in other ways, so this just added to the suspicions that I had," she said.
Rooney admitted telling a "fib", informing Vardy that it was probably her children who always played with her phone.
After reinstating Vardy as a follower on her private account, Rooney started posting a string of fake stories and changed the settings so that only Vardy's account could see them.
Over the course of the next few months, three of the stories appeared in the Sun newspaper, prompting Rooney to reveal her findings on social media.
The court heard that Rooney initially wrote her "Wagatha Christie" post with a pen and paper in her notepad, before typing it up and sending it to her brother who manages her social media accounts.
Rooney said she chose not to approach Vardy privately with the accusation because she felt she would try to "cover it up" and "would not be truthful".
After she shared the post, the court heard that Vardy texted her saying, "what the f*** is this?", to which Rooney replied: "You know what it is".
Vardy then asked Rooney: "Who is your lawyer?"
Rooney, who said she found the threat of legal letters and lawyers intimidating, was surprised that the story became "as big as it has been".
The mother of four also discussed her rise to fame and reports of her husband's inappropriate behaviour, telling the court: "There's been a few unfortunate things that have happened in my life and they have got publicity".
"It's happened quite a few times. We've dealt with it as a couple and as a family."
She accepted that she has taken media opportunities that have come her way, but she "never asked for" publicity, adding: "I was thrown into it, and I've worked with it".
"I wanted to continue at school but the pressure was big at a young age," she said.
The hearing, which is expected to conclude on Thursday, continues.