The HGTV star filed for divorce from her second husband in November.
The former couple married in Dec. 2018 and share a 1-year-old son, Hudson. Christina, 37, is also mom to Brayden, 5, and Taylor, 10, with her ex-husband and Flip or Flop co-star, Tarek El Moussa.
"I think everybody knows this was not my decision. It really hit me hard," Ant, 41, tells People. "If you ask anybody that knows me properly, they know that I give myself fully. I had so much love for her."
Christina announced her separation from Ant in September. At the time, Ant stayed off social media for a bit, before taking to Instagram to write that he had "remained silent while holding on to hope."
"I never gave up on us," he said in the post. "I pray Christina's decision brings her happiness."
Christina filed for divorce from Ant in November. During that time, Ant tells People, he was in a "very dark place," which he only escaped after signing up for a five-week program that teaches newly single people to "grieve your relationship so you can let it go." He also lost more than 20 pounds.
"I reached this turning point... I had the choice to dwell on it, or move on and work on myself," he says, noting that the program taught him that "nobody controls me but me."
"It’s up to me to empower myself and realize how incredibly worthy I am of healing," he says. "... Not only have I improved my mental health, I've actually made a real conscious decision to go and improve my physical health, as well. I mean, for the first time in my life, I'm actually now taking vitamins!"
While Ant acknowledges that his split is and will continue to be "a process," he's hopeful for the future.
"The thing about healing is sometimes you feel like you’re making daily progress, and then, from nowhere, your legs get taken out, and you feel like you start again," he says. "But I'm certainly making steps towards healing, even if it's really slow."