"I'm not engaged and I don't have a ring and I haven't been proposed to," Aniston told People magazine.
The actress said she normally ignores celebrity gossip, but she has been getting phone calls from Greece where her aunt has been accused of lying, she said.
Her relationship with Vaughn -- who she met last year filming "The Break-Up" -- is on.
"We're just being," she said. "We're having a good time."
Aniston became concerned when the story started being reported by the mainstream media, including CNN and NBC's "Today."
"Tabloids are going to lie all the time. You're prepared for that," she said. "But it's the news."
"Well, we need to trust what our newscasters are saying when we have this horrific situation that's actually taking place in the world," Aniston said.
"The American people need to believe (the news)," she said. "Please. Get it together."
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