By Joey Bartolomeo
March 12, 2012 12:00 PM

After a busy week of promoting her summer film Battleship, executive-producing a TV fashion show, and a magazine photo shoot, Rihanna hit the London club Aura in the wee hours of Feb. 27. “I love this club! DJ on point!” the seemingly carefree singer tweeted.

But some who know Rihanna and are close to her are concerned. Just a week earlier, she had released a remix of her song “Birthday Cake,” recorded last month with her ex-boyfriend, R&B star Chris Brown, the man who notoriously left her bloodied and beaten after an argument in his Lamborghini three years earlier. The reaction was immediate among those who haven’t forgotten that Brown, 22 (who had also just posted a remix of his song “Turn Up the Music” featuring Rihanna), had pled guilty to felony assault against the pop star, 24. “My God, where is the self-respect??” asked one of her Facebook fans. Wrote another: “This is really just a cry for help.”

Rihanna’s relationship with Brown goes beyond the recording studio. Says a source who has worked with her: “It started with texting. They talk on the phone now and then too.” Over the past several months, “they’ve hung out a lot at her L.A. home,” adds another source. As one Rihanna pal puts it, “They love each other, pure and simple. Looks like this is the beginning of them getting back together.”

A restraining order was eased in February 2011. “They’ve always been in contact but hid it,” says a music insider. “When the order [was eased], they didn’t care anymore.” In fact, Brown-who’s dating model Karrueche Tran, 23-went to Rihanna’s Feb. 13 birthday party in L.A. “She was really happy to see him,” says the Rihanna source. “She thrives off being the girl everyone wants. She likes to cause an uproar.”

Attention may not be the only allure for her. “It’s very common for an abused woman to try again,” says Rita Smith, National Coalition Against Domestic Violence executive director. “Most of them love [their abusers] and want that person to have changed.” Notes Harvey Mason Jr., who coproduced Brown’s “Turn Up the Music”: “Rihanna has chosen to forgive him.” Her ex, who told PEOPLE he was “ashamed” about the attack, has “put his life back together,” says a Brown source. “Isn’t it up to the [victim] to decide if they can trust again?”

Perhaps a more important question: How reformed is he? Brown may face a robbery charge after allegedly snatching a phone from a fan during a Feb. 19 incident in Miami Beach; if he’s charged, the L.A. County probation department could consider a probation-violation hearing. Regardless, “some people around her aren’t happy and are trying to stop [the relationship],” says the Rihanna pal. “But it’s looking like it can’t be stopped.”