In a sneak peek of Wednesday night's episode, the 23-year-old carpenter and self-proclaimed "ladies man" was caught repeating the rumours about Ali and her Bachelor In Paradise ex Grant Kemp.
"He made up stories that he knows people that are your friends that apparently emphasise the rumours were true," Charlie Newling tells Ali.
"Let me at him!" Ali says before confronting Nathan. "I heard you were saying really disgusting things about me!" says says in the promo.
"I heard you were saying really disgusting things about me... and I want to know what you were saying," we say Ali tell Nathan.
Charlie then goes off on Nathan for spreading rumours about her, and the two men get into a verbal argument.
"I really feel sorry for Ali if she even ends up with you," Nathan says to Charlie.
The Bachelorette Australia continues Wednesday and Thursdays at 7:30 on TEN