NEW PICS: Ramona Singer’s Alleged Homewrecker Kasey Dexter Posts Photos of “Dear Friend” Philip Seymour Hoffman

It looks like the so-called other woman in Ramona and Mario Singer’s marriage is quite the social butterfly and the reality TV house hubby isn’t the only one she’s met in the celeb circle of NYC.

Kasey Dexter, who the New York Post reported was having an ongoing affair with the Real Housewives of New York City star’s husband of more than 20 years, has been posting pics on Facebook of her celebrity encounters, including cozying up to Philip Seymour HoffmanCameron Diaz and Olivia Munn.

She even claims to have been a “dear friend” of the late actor, who died of an apparent heroin overdose last Sunday.

“So sad to lose one of the most brilliant actor and dear friend Philip Seymour Hoffman,” she wrote along with two photos of her and the 46-year-old star. “May you rest in peace. The world will miss you and forever remember your spirit.”

The 32-year-old fitness instructor didn’t end there when chatting online with pals about her bereavement: “This was tragic,” she said of his sudden passing.

“Such a sad day. Prayers and thoughts go out to the family,” said Kasey, who’s been described as a “socialite,” only our sources say she’s far from it.

Using Facebook like her own digital diary, Kasey continued to let it all out, and it wasn’t all about the late actor’s sudden end. She added: “Sad couple days for other reasons” on Feb. 2.

Maybe that’s because according to Star, Mario has now cut off all communication with Kasey. Clearly she’s having a bad week because she uses the same tone (but with hugs and kisses!) to describe her emotions about all those blabbing about her in the press: “I find it sad that childhood friends and even close friends choose to sell stories and private pictures…of me. I feel sorry for you both…today is a new day! Xo,” she wrote Thursday.

When the Post first broke the news about their months-long tryst back in October (that even ended up with her pregnant and getting an abortion), Mario broke it off with the Andover, Mass. native, only to heat things up again shortly after, CB! previously reported.

So when Ramona reportedly caught the two together at her Hamptons home last month, she exploded, the cops came, and that was the last straw.

An eyewitness previously told CB! Mario was “all over” Kasey at a Hamptons party last summer… with Ramona in the same room! The reality star even denied marital problems to those in her inner circle, so we were informed.

That is, until Ramona filed for divorce one week ago.

Get to know Kasey Dexter, all her supposed celebs friends, and a her penchant for sexy selfies in the CB! gallery above.