Catherine Giudici and Sean Lowe
04/16/2013 at 07:15 AM EDT
and his final rose-winning fiancée
, Catherine Giudici from The Bachelor
, are apparently still on and going strong.
Despite rumors of a rocky romance, Lowe, 29, tells PEOPLE, "We are happy and could not be better."
Chatting backstage after a successful turn in the ballroom
with partner Peta Murgartroyd on Dancing with the Stars
, Lowe also addressed general rumors he encounters, including ones that he's a diva on the set of his latest show.
"Nobody knows anything outside of me and Catherine and the people who are closest to us," he says, calling tabloid gossip "so ridiculous."
Adds Lowe, "Typically, we don't read [tabloid reports], but if we're checking out at the grocery store, we'll see them and we'll flip through and laugh. It's all nonsense. It's all fictional."
Giudici – who has consistently cheered her man on from the live audience at DWTS
– is the first person Lowe called when he was offered the gig.
"I wanted to make sure she was okay with it and she said, 'Absolutely, I'm going to support you,' " he says. "I couldn't ask for anything better. I couldn't do this without her."
As Lowe spoke adamantly about his relationship, Murgatroyd chimed in, saying, "I can vouch for that, too. I can really vouch for that."