updated 08/10/2014 AT 5:00 PM ET
•originally published 08/11/2014 AT 8:00 AM ET
Mario Singer and Kyle “Kasey” Dexter looked “very flirty” at the Women’s Health Party Under the Stars in Bridgehampton, New York, on Saturday night, an onlooker tells PEOPLE. The two were also photographed together in Sag Harbor.
“All marriages hit bumps, some bigger than others,” the businesswoman told PEOPLE in April. “We have a history of 25 years together and we have been very happy.”
But on Thursday, Ramona Tweeted that they had split again.
“I have decided to move on with my life without Mario. I tried my best to make my marriage work. I am excited for the new chapter in my life,” she wrote in her post.