"I've never gone back in the ex category. No," Christina, 33, told E!'s Daily Pop, adding that she doesn't plan to start now.
The couple separated around this same time last year, but Tarek didn't file for divorce from Christina until January 2017.
Despite their split, the couple continues to work together on their HGTV reality series Flip or Flop while co-parenting their two young children -- Taylor, 6, and Brayden, 20 months.
"We're good. We're actually really good," Christina said of her relationship with her ex.
"We've been separated for almost a year now. We've made a lot of progress in our relationship. We're just really focused on the kids, and we're really excited to start on 15 new episodes of Flip or Flop."
The pair has been spending time with each other on and off theFlip or Flop set. Late last month, Christina and Tarek, 35, wore matching black ensembles and walked the red carpet arm-in-arm at the 2017 Daytime Emmy Awards together, smiling and posing for cameras.
Christina and Tarek presented an award onstage at the Emmys.
"It was actually great," Christina told Daily Pop of the experience. "That was our first time on the red carpet, period. It was really fun. We had a great time presenting and hopefully we're able to do it again soon."
The reality TV stars and house flippers publicly announced in December 2016 they had split after seven years of marriage.
Christina and Tarek have since dated other people, with Tarek being linked to one of the family's former nannies, Alyssa Logan, and Christina having briefly dated their former contractor Gary Anderson.
Rumors also recently swirled that Christina was involved with NHL player Nate Thompson, however, their alleged romance didn't seem to go anywhere.
"We need to get along for the kids and for our sanity," Tarek recently told Us Weekly.
"There haven't been fights. We have fifty-fifty custody now. She's a great mom and I like to think I'm a great dad. Sometimes she or I will say, 'I need them for an extra day or two.' We're both flexible."