Derek Hough Knew He Was Ready to Propose When Calling Hayley Erbert His Girlfriend 'Felt Really Wrong'

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Derek Hough's decision to propose to longtime girlfriend Hayley Erbert came after a pivotal realization.

In a joint interview, the couple told PEOPLE exclusively how it's been an adjustment to call each other "fiancé" and "fiancée."

"[I was] so used to saying boyfriend. The other day I was at the vet with my dog and I was like boyf—iancé?" said Erbert, 27.

"That was one of the big signs for me knowing that it's definitely time [to propose], because I called her my girlfriend at some event and it felt really wrong," shared Hough, 37. "[It was] almost like a cheap word for how our relationship is. So, I was like, it's a good sign."

RELATED: Derek Hough Details the 'Covert Op' — Including a Helicopter! — He Set Up to Propose to Hayley Erbert

Anee Atelier

Hough and Erbert announced their engagement after seven years June 2 on Instagram. Behind the scenes, Troy Williams of Simply Troy Lifestyle + Events had helped the Dancing with the Stars judge plan the special moment when he would pop the question with a ring designed by Paris Jewellers.

"It's been a long time. We didn't sit down and say, 'It's time,'" he continued. "It was more just we joked around saying, 'Hey, we should do this at our wedding or we should have this person at our wedding or this and that.' She'd be like, 'Babe, we're not even engaged yet.'"

Erbert pointed out that it was "a gradual conversation of future plans" between them, saying it "wasn't really like a set situation."

RELATED: Derek Hough and Hayley Erbert's Relationship Timeline

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Given their deep history together, Hough knew he had to make the moment extra special, so he chose a place extremely close to their heart — their shared home.

"It's funny, I went back and forth so much on so many different locations. Hayley and I have some special places and I would bounce around, and I had things planned. Last minute, I just kind of changed," he said.

"I was like, you know what? We already do all these amazing things. We travel around the world and have adventures, so we're always so happy to come home and be home, and that's really where our relationship really strengthened and was made concrete," he added. "I was like, I'm gonna transform our house."

Add in 250 oversized candles, 1600 roses as well as orchids, white peonies and pampas grass as an elegant backdrop, and the pair had a recipe for an unforgettable proposal to start "the beginning of forever."

"After she said 'yes,' it was just everything," recalls Williams, who chose the floral color palette to match their home. "[It was] such a special, beautiful moment and just so them."