"I love him and I'm really sad, but I have to look out for me," Harris told Us.
"We're both kind of resetting. Jillian isn't happy and I'm definitely sad about the whole thing, but we've got to work through some things on our own if we decide to move forward," Swiderski added.
"[They] are taking some time apart to re-evaluate their relationship," an ABC source subsequently toldPeople.
Swiderski proposed to Harris after she selected him during The Bachelorette's final fifth-season Rose Ceremony, which was filmed in Hawaii in May 2009.
However shortly after the finale aired in July, two former Swiderski girlfriends came forward and claimed they had been -- unbeknownst to each other -- dating and sleeping with Swiderski before, during and even after the filming of The Bachelorette's fifth season.
Earlier this year, the couple -- who previously canceled plans to announce a wedding date on January's The Bachelor: On the Wings of Love premiere -- had said they were considering following in the footsteps of The Bachelor thirteenth-season couple Jason Mesnick and Molly Malaney and turning their wedding into a televised special.
"We're going to use Molly and Jason as a guinea pig, we're going to see how that goes down," Swiderski told Us before ABC airedThe Bachelor: Jason and Molly's Wedding in March. "We've gotten to know those guys."