Ozzy Osbourne's mistress suing Kelly Osbourne for defamation

Kelly Osbourne has been slapped with a lawsuit from her father's former mistress after posting her contact details online.

Ozzy Osbourne's 34-year marriage to his manager wife Sharon hit the rocks in May (16) after the rocker's alleged fling with Los Angeles-based hairstylist Michelle Pugh went public, and Kelly made her feelings about her dad's mistress clear by taking to social media and putting her on blast.

The TV personality lashed out on Twitter, and posted a Los Angeles phone number believed to belong to Pugh, who went into hiding as soon the affair news was made public.

After receiving some criticism from followers who suggested she take out her anger on her dad instead of Pugh, she fired back, "My father is almost 70 ever heard of elder abuse?"

Ozzy and Sharon initially split, but they have since reconciled, and on Wednesday (03Aug16), as a tell-all interview with Pugh was published in People magazine, a representative for the Black Sabbath frontman revealed the musician was undergoing "intense" therapy for sex addiction. The spokesperson also admitted Pugh wasn't the only woman Ozzy had romanced behind Sharon's back in recent years.

Now Pugh, 45, is taking aim at Kelly for the backlash she suffered as a result of the headline-grabbing tweet.

In legal papers filed in Los Angeles County Superior Court, and obtained by TMZ.com, the hairstylist has slammed Kelly for suggesting she manipulated 67-year-old Ozzy, insisting he was the one who initiated the romance in 2013 and kept the relationship going until May (16).

Pugh claims she had a cease and desist letter sent to Kelly demanding she take down the post, but it wasn't deleted for almost a month, causing her to be "slut-shamed, bullied and harassed". She also lost out on business as a celebrity stylist as a result, and is now suing for defamation, intentional infliction of emotional distress and public disclosure of private facts.

"I am a private individual. I am not a celebrity," Pugh tells People. "My private life is off limits."

Kelly, 31, has yet to respond to the legal action.

Her mother Sharon opened up about Ozzy's sex addiction treatment on her U.S. daytime show The Talk on Wednesday, admitting she was embarrassed and "mortified" at how his struggle almost tore apart their family.

However, she claimed she was "proud" of the rocker for admitting his mistakes and enrolling in a treatment programme.