Is it too late now to say sorry? In Vanderpump Rules' Monday, February 29, episode, Stassi Schroeder learns the hard way that not all of her former friends are ready to forgive and forget, as seen in Us Weekly's exclusive sneak peek.

The clip shows Schroeder, who recently made her first season 4 appearance on the Bravo series, telling onetime bestie Katie Maloney that she regrets mistreating her, given that other friendships aren't as meaningful as her relationship with Maloney was.

"No s--t because your friendships are fluff with people," Maloney fires back. "I don't think friends are disposable, period, or people are disposable or anything, and especially me. I'm sorry, but I was a f--king amazing friend to you."

The pair have been on the outs since Schroeder accused Maloney of siding with Scheana Marie Shay last season in the brouhaha surrounding the former Sur server's sex tape.

Schroeder admits that her behavior was "wrong" and breaks down in tears when Maloney still won't accept her apology.

"That's great, but too little, too late," Maloney continues. "I've got obviously amazing people in my life. You know, I just wouldn't have time to go through that again. I would be a damn fool."

Watch their heated conversation in the video above.

Vanderpump Rules airs on Bravo on Mondays at 9 p.m. EST.

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