04/22/2014 at 01:00 PM EDT
Is Ramonja no more?
Hold the Pinot Grigio: A sneak peek at the next Real Housewives of New York City
suggests best buddies Ramona Singer and Sonja Morgan are on the outs.
Singer, 56, missed Morgan's "cabaret-meets-soft burlesque"
show a few episodes back while vacationing with her daughter in South Africa. Once Singer returned
, she apparently unfurled less-than-flattering comments about Morgan's performance – and the toaster-oven entrepreneur isn't putting up with her friend's criticism.
"I have fabulous parties to go to tonight where people appreciate me, who I've known just as long if not longer than you, who think I'm talented," Morgan, 50, rants in the clip, as Singer approaches her at a social gathering.
For once, a wide-eyed Singer is speechless.
"I'm sorry, I should have zipped it," she apologizes. But Morgan won't have it.
"You couldn't handle a day in my life, Singer. Not one day. You would fall apart. And you don't have a lawsuit, you don't have a divorce, you don't have a custody battle, you're not a single mother," she spits. (Ironically, Singer did file for divorce
from husband Mario after the season stopped taping.)
"I'm keeping my s--- together, and I need you to be a friend and not make those kind of negative comments, because you should know better than anyone in this room," Morgan finishes.
Watch the drama unfold firsthand – and see what happens next during an explosive Fourth of July weekend in the Hamptons – when The Real Housewives of New York City
airs Tuesday at 9 p.m. (ET) on Bravo.