Ben Simmons’ breakup is getting pretty messy

BEN Simmons is being publicly attacked by the family of his ex-girlfriend amid accusations he cheated on her with Kendall Jenner.

TMZ suggested "the woman in (Simmons') car looks a lot like Kendall Jenner".

BEN Simmons is getting a rude introduction into the life of the Kardashians.

The 21-year-old basketballer from Melbourne, Australia, is now being followed by TMZ cameras and having wild accusations slung at him on Twitter.

That’s the price of being linked to supermodel Kendall Jenner, who Simmons has reportedly been spotted spending time with after breaking up with pop star girlfriend Tinashe.

Tinashe’s brother, Kudzai, slammed Simmons on Twitter after the New York Post broke the news he was dating 22-year-old reality star Jenner, accusing him of breaking his sister’s heart and cheating.

“Never met you before in my life,” Kudzai tweeted. “Days after u break my sis heart u do this … ppl all lied on her talking fake news about my sis “doing kardashian s***” u cheat on her w a Jenner.”

Kudzai claimed Simmons and Tinashe only “broke up” on Monday (AEST). “Sorry for blowing up y’all twitter everyone,” he added. “It was actually the only way to defend my sister against all this bulls***.”

Tinashe's brother Kudzai attacked Simmons on Twitter.

Tinashe’s grandmother also tweeted in her defence. “Dear twitter fans and fans of Tinashe, I have decided to leave Twitter because of all the hate and lies about Tinashe,” she wrote. “You must realise that I love her very much but as a family member I really can’t call out all the lies and hate because some things should not be shared.”

LISTEN: Ben Simmons, Kendall Jenner and the NBA Finals - The Splash podcast

“For all you wonderful fans out there I thank you for all your support and love,” she added. “I know you wish her the best and I applaud all of you. I just don’t like thinking I’m in Junior High again. I’m just too old for this. All my love. Grandma Tinashe.”

Neither Simmons or Tinashe have commented publicly on their breakup, although the pop star did post this photograph on Instagram with the caption: “I set the bar, I’m the f***in bar.”

"I set the bar, I'm the f***in bar."

TMZ posted a video of Simmons getting into a car outside the Waldorf Astoria Beverly Hills with a “mystery woman” on Tuesday (AEST).

“Our sources say Simmons and the mystery woman had a bite to eat together,” TMZ wrote. “We’re told the woman tried like hell to stay low key — using her hoodie to cover her face.

“If that really is Kendall (and it really seems like it is) … welcome to the Kardashians, Mr. Simmons!”

It came after an insider familiar with the duo told the New York Post the romance has been going on “for a few weeks.”

Another source said the pair was spotted this week on a lunch date at the Beverly Hills Hotel. And a third source said Jenner, 22, and Simmons, 21, were seen last week in Manhattan with a group of friends at the clubby Bowery restaurant Vandal.

“Security measures seemed to have been taken to ensure Kendall and Ben enjoyed their night hassle free,” said a witness. “They were smiling the night away with their friends.”