The 37-year-old reality star -- who's been chronicling her recent 300-pound weight loss on her WE tv show, Mama June: From Not to Hot -- sat down for an exclusive interview with ET's Jennifer Peros on Tuesday, where she dished on the motivation behind her weight loss journey.
"I wanted to also show Sugar Bear," Mama June shared. "He really made me feel like s**t [and] I wanted to show him, 'Hey, I can do [whatever] I want to do'… I wanted to show him, like, I am actually worth it."
Mama June and her ex split up in September 2014. Not long after, Sugar Bear sparked up a relationship with a new woman, Jennifer, and according to Mama June, it was this development that motivated her drive for a revenge body.
However, now that she's slimmed down to a size 4, she said she's not really putting much thought into her ex's reaction to her weight loss.
"I don't know and don't really care [what he thinks]," she admitted.
As documented on her new reality series, Sugar Bear actually invited Mama June to his wedding, which ended up being the first time he saw her after she underwent $50,000 in cosmetic surgery to slim down.
According to the former Here Comes Honey Boo Boo star, going to her ex's wedding was understandably "awkward."
"I told him that he made me feel like s**t, honestly," Mama June shared.
While their relationship looks strained on the docuseries, Mama June says things between her, her ex and his new wife are actually much worse in reality.
"The show is a mild version of what's actually [happening] in real life," she explained.
Since their split, Mama June said Sugar Bear has mostly kept out of contact with their daughter, Alana "Honey Boo Boo" Thompson, and that their relationship has been mostly "non-existent."
"He has nothing to do with Alana," she explained. "They don't see each other at all, they don't call or anything."
Mama June's adorable 11-year-old daughter also sat down with ET, and gave an insight on her strained relationship with her dad.
"He calls me every once in a blue moon," Alana explained. "So if there's a blue moon outside, he's going to call me."
And when he does call, Mama June says he "doesn't even know what to say to her."
Alana recounted how, during a recent conversation with Sugar Bear, she offered to come over to his house to help him mow the lawn.
"I was like, 'I'm [gonna] need a ride mower,' and he said, 'You're gonna need a push mower because it wouldn't hurt,'" Alana recalled.
"[He was saying], 'It wouldn't hurt if you lose weight,'" Mama June explained. "I think that was the most ignorant thing that he ever told her. I would never say that… I mean, he pisses me off."
"I think after this show people are asking me what [kind of person he] really is," she added. "I'd say not Father of the Year material."
Mama June also got candid about her current love life, but the mother of four said she really doesn't have any interest in finding a new love right now, and that it's been tough meeting men "that are genuine."
"I gave it up. It isn't worth it," she shared. "There's jerks and douchebags and you never know who is gonna be here for you."
Mama June: From Not to Hot airs its season finale Friday at 9 p.m. ET/PT on WE tv.
WATCH: Mama June's Weight Loss Surgeries Revealed -- How She Went From 460 Pounds to a Size 4