The one-time BFFs are airing their dirty laundry on Twitter, and the latest accusation has Hilton (real name Mario Lavandeira Jr.) repeatedly issuing a statement about the whole thing on his blog.
This isn't the first time Hilton has gotten into it with a celebrity. His list of feuds includes spats with will.i.am., Khloe Kardashian and Miss USA runner-up Carrie Prejean.
But let's rewind on the current kerfuffle, shall we?
The exact origins of the Hilton-Gaga feud are unclear, but Hilton has repeatedly published tweets and blog posts with criticisms about Gaga's latest single, "Applause," calling it "meh" and pointing out its lackluster performance on the charts, especially when compared with Katy Perry's "Roar." Perry recently ousted Lady Gaga as the most followed female celebrity on Twitter too.
Gaga's fans, also known as Little Monsters, did not take the detracting lying down, unleashing a flurry of homophobic abuse at the openly gay blogger and his new son.
The "Born This Way" singer also posted a scathing tweet regarding a pic she'd reportedly received from Hilton following a hip injury at the beginning of the year that landed the singer in a wheelchair.
"Still have the text Perez sent me of me in a wheelchair w the words KARMA written across + Madonna pointing a gun at me. Day of my accident," she wrote on Aug. 16.
Again, the Little Monsters came out in droves and continued to threaten the gossip writer.
Hilton recently announced that he was relocating his family from Los Angeles to New York. Apparently he went house hunting in the Big Apple this weekend, when Gaga said fans tipped her off about him viewing an apartment in her building. That's when she lost it and lashed out on Twitter on Sunday.
"@perezhilton STAY AWAY FROM ME + MY FAMILY YOU ARE SICK TRYING TO RENT AN APARTMENT IN MY BUILDING TO STALK ME. LEAVE ME ALONE!!!" she wrote in tweets that have since been deleted.
"DO I NEED TO BE SHOT IT IN THE HEAD FOR PEOPLE TO UNDERSTAND THAT HIM AND EVERYONE ELSE THAT HARASSES ME HAS GONE TOO FAR? IM A HUMAN BEING"
However, a Hollywood Reporter source said Hilton had been scheduled to view an apartment in her building without knowing she lived there.
Later that day, Hilton stood his ground, posting a statement titled "A Statement on Lady GaGa's Lies" under the "Personally Perez" section of his blog.
In the statement, he says that he lived in the Big Apple for six years in the mid-1990s and again last year for three months while he was doing an off-Broadway show.
"I'm a new father and I am primarily focused on my family and where we will be most happy," he said. "I love New York and that is where me and my growing family want to call home right now. Sunday, my realtor showed us a list of possible apartments to rent. I learned only after the fact that Lady GaGa lives in one of the buildings we looked at, and she was across the country in Los Angeles when I viewed that building.
"After a day of innocent house-hunting, I am devastated and my heart hurts that my former very good friend, a person I used to call my 'wifey' and traveled the world with, is making very public and very untrue allegations about me on Twitter. While it is still too painful for me to go into detail about why I chose to no longer make her a part of my life, I will say that I am a critic and not a 'stalker'. Any allegation that I am stalking her, based on a day of house hunting with my baby boy and my mother, is utterly false, defamatory and now appears to be putting me and my family in danger."
Hilton said he would "continue to be a critic" and hoped that her fans would stop sending him death threats.
Gaga's fans continued to attack the blogger, which was made clear when he constantly retweeted the sometimes vulgar messages. One carried the hashtag #OperationKillThePig, others told him to kill himself and still more threatened to kidnap his young son.
"The suggestion that I pose a danger to Lady GaGa is preposterous," he said. "If her fans want to send a message of support to Lady GaGa, they should buy her music. Notwithstanding my feelings about our personal relationship, I do wish Lady GaGa happiness and continued success and I assure you my family house hunting has nothing to do with her."
Hilton returned to Twitter on Monday, reposting a link to his statement but also sharing his current state of mind.
"I can't sleep. I am literally sick to my stomach. Not playing any ... games here. I am afraid for my ... safety and that of my son," he wrote, adding, "I know some people are sick, and addiction will make you act up, but people need to take accountability for their actions!!!!"
"I know it's hard to see our idols/friends/people we looked up to as less than awesome. But sometimes those people are so hurtful!" he added.
Gaga dropped the video accompanying "Applause" on "Good Morning America" on Monday amid the controversy. And despite all the threats he had been receiving, celebrity chatterbox Hilton admitted that the video was "visually very compelling" but still thought it was "sadly much better than the song."
Once a critic, always a critic.
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