Watch Nikki Bella and John Cena's Emotional First Conversation After Calling Off Their Wedding

"John, I mean, he's like a frickin' magnet to me."

Emotions were running high when John Cena and Nikki Bella reunited for the first time after calling it quits.

In a sneak peek of Sunday's Total Bellasthe pair run into each other backstage at the taping of WWE's Raw 25th anniversary event in New York City, and while they cordially share a hug, the awkwardness is felt. 

"John, I mean, he's like a frickin' magnet to me and it's like my heart sinks so deep into my stomach," Nikki says to camera. "Like, I feel like I don't even know how to breathe. [It's] as if my lungs are filled with fluid."

Upon speaking with her ex-fiance, Nikki touts, "You didn't even call or text me yesterday."

"I'm supposed to stay away from you," John replies. "It's taking every fiber of my being not to text or call you. I'm just trying to do the right thing."

"I miss you so much," John tells his ex. "I miss you too," she replies.

In a separate preview for Sunday's upcoming episode, Nikki breaks it to her family that she and John have called off their engagement.

"I feel like such a huge piece is just missing from me," Nikki tearfully tells her twin sister, Brie. "It's just weird, first morning in six years not to talk to him, you know? ... Our life is one, that's what's so hard."

A major problem for the pair was apparently Nikki's desire to have a baby, while John did not want to have kids. 

"He sent me this text last night, and he goes, 'The day you become a mom and look at your baby, I'm expecting to get the first thank you text,'" Nikki continues. "But it's like, I wanted him to be the father of my kids."

Earlier this month on the Today Show, John said that he had changed his mind when it came to having children. 

"I'm willing to go back on all of these things I said, and a lot of things I was holding on to just out of stubbornness -- 'I won't have kids' -- and it took a really strong look in the mirror for me to be like, 'Why,'" the WWE star said. "This person is my number one, and it's something that's very valuable to her, and of course we can do this ... all of that switched because I love her. She's my number one and I just want to make her happy ... and right now, she's happy." 

Nikki also exclusively told ET earlier this month that "it's going to take time" for her and John to possibly reconcile their relationship. 

"John and I, we absolutely love each other and we care about each other a lot," she explained. "We are best friends and, right now, we're both giving each other time separately and maybe there's hope that we reunite in the future."

Here's a look at when Nikki told her family that the wedding had been called off: