Sienna Miller and Balthazar Getty
While Sienna Miller
hangs in L.A. with still-married beau Balthazar Getty, her mother is defending the couple's relationship and calling for an end to the "feeding frenzy" surrounding the scandal.
"You can't understand how a woman seeing a man who has been separated from his wife [Rosetta Getty] for months can cause such a scandal," she told the U.K.'s Daily Express
newspaper. "It's awful, I can't tell you. You wonder when it's all going to stop."
Close friends of Rosetta Getty, 38, have told PEOPLE that the couple was "in no way separated
" when the Brothers & Sisters
star began dating Miller. One friend said: "Any implication otherwise is an absolute lie. Balthazar's affair has been utterly devastating to Rosetta and her family."
On July 21, Getty released a statement announcing he and Rosetta are separated
, though no legal papers have been filed.
"Yes, they're living separate lives at the moment – because of his shenanigans," says another pal. "It's disappointing that [Getty and Miller] are flaunting this so publicly. There are four children involved. Their oldest, Cassius, is mature enough to understand something's not right."
While in L.A., the couple have been spotted shopping for clothing, going on coffee runs and having a double date with producer Jerry Bruckheimer and his wife Linda at the popular Malibu eatery Taverna Tony's.
Owner Tony Koursaris tells PEOPLE, the group "all had a great time," noshing on hummus, salad, Greek meatballs, fish and soup. Says an employee at a Malibu supermarket where they shopped together Aug. 9: "They were holding hands and looked in love."
Rosetta Getty, meanwhile, is on a long-planned trip with the Getty family on its yacht, and has plans to meet with potential partners for her clothing line, Riser Goodwyn.
Reporting by PERNILLA CEDENHEIM