Who wants to know? Bethenny Frankel tries to defend how she handled the situation involving Luann de Lesseps' fiancé kissing another woman in the third part of The Real Housewives of New York City's season 8 reunion on Wednesday, September 14, as seen in Us Weekly's exclusive sneak peek.

The Bravo series' preview clip shows host Andy Cohen asking Frankel why she told costars Ramona Singer and Carole Radziwill before de Lesseps herself about the pics Frankel received of Tom D'Agostino Jr. making out with someone else.

The countess, 51, chimes in with, "So they could talk about me behind my back and make me look like a village idiot."

Frankel, 45, then says, "I think I explained it pretty well on the show. I explained that I don't know if she's the person that you're supposed to tell. I think this brings up a concept of, 'Would you want to know?' and Luann ultimately said she's not the person who wants to know."

But this explanation doesn't hold water for de Lesseps. "Of course I want to know," she fires back. "I want to know in a respectful way from a dear friend who has my best interests in mind, OK? Not from somebody who doesn't respect me, who called me the names that you did, and then on top of it, shares it with me [after] the whole world.… That's not a girl who's looking out for me. That's a girl who has her own agenda."

After de Lesseps lays into Frankel for having previously asked her if she and D'Agostino were "monogamous," the Skinnygirl mogul gets out of her chair to exit.

"I'm going to leave," Frankel tells the group. "I don't want to do this anymore."

Watch the contentious clip in the video above. The Real Housewives of New York City airs on Bravo Wednesdays at 9 p.m. ET.  

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