The actress detailed in the May issue of Vanity Fair that the “Magic Mike XXL” star reached out to her right after she announced her split from ex-fiance Nick Loeb.
"But we started talking a lot, and then he showed up in New Orleans," she continued. "Since then we’ve been inseparable."
Vergara, who plans to wed Manganiello later this year, says her 38-year-old fiance is near perfect for her.
"There’s nothing about him I’d change other than the fact that he’s four years younger than me," Vergara, 42, added.
Vergara has been open about having more children in the past, but says, ultimately, the decision to expand her family is up to Manganiello.
"My son, Manolo, is 23 years old, which is going to be really weird if I have another baby. But, you know, Joe wants babies and if it's going to make him super-happy, then...," Vergara said.
The two stars became engaged in December.