"I've never even looked back for a second on my decision," Hebert tells PEOPLE in the latest cover story.
In fact, Hebert, 26, credits Rosenbaum, who proposed to her in Fiji on the ABC show's Aug. 1 finale, with helping her recover from her ill-fated romance with two-timing contestant Bentley Williams.
She also says her relationship with the 34-year-old New York construction manager didn't truly begin until the cameras went away.
"Our relationship really started after we left the show," she says. "The show made us stronger than if we'd met on the outside."
Like the many Bachelor and Bachelorette couples the preceded them, watching the events of the production play out each week – specifically Hebert's heartbreak over bad boy Williams's sudden departure and her intense affection for runner-up Ben Flajnik – challenged their union.
"It stings," Rosenbaum admits of watching Hebert court her other potential suitors on the show.
But, Hebert says, their open communication is what fortified their relationship – both over the difficult-to-watch subject matter and the relentless attacks they've received from the tabloids.
"You make it through something like this together, you can make it through anything," Rosenbaum says.
For more on the couple's engagement, their relationship challenges and their future plans, pick up the new issue of PEOPLE, on newsstands Friday
Mitch Haddad / ABC