Vannessa Cross is finally ready to start therapy again and work through her issues with eating and weight loss. But the prospect of digging deep into her past — and share her "horrible secrets" — is terrifying.

In this exclusive clip from Monday's episode of 1000-Lb. Best Friends, Cross and her best friend Meghan Crumpler meet with their bariatric psychologist, Dr. Connie Stapleton, again after taking a break.  

Cross, 44, has made major changes since she last saw Stapleton — she's finally moved out of her sister's house and really trying to stick to her diet, and Stapleton tells her "that's huge."

"It is, extremely," Cross agrees. "It's been mostly positive, but, in all honesty, I'm struggling with my diet right now. Because losing weight, a lot of things come up. You think about a lot of things because I get angry and upset because I don't have the food I want, so my brain starts going into, 'Okay, let's reminisce.' "

Stapleton tells her, though, that "that's a lot of great awareness, and it sounds like you're ready to start talking about it."

But in a separate solo interview, Cross says that she's worried about what will come up if she starts regularly doing therapy.

"I'll be honest to say that I've been having some nightmares about some of the things I've done in my past," she says. "I have some horrible secrets that I've been holding on to for years. And Meghan's one of the few people in the world that knows about it. So, when it comes to talking to a therapist, that scares me."

Back in the therapy session, Cross tries to explain that to Stapleton.

"Since our last visit, I really did soul searching. And I've come across, just things that I've done — some things [Meghan] knows about, some things she don't — and I don't know how to work through the things I've done in my past," she says, starting to cry. "Things I've just — physically and emotionally had to do."

While Cross doesn't reveal what her secrets are in the clip, she's previously talked about her issues with food on the show. During a confrontation with her sister Jakie, Cross gets frustrated as Jakie tries to get her to eat doughnuts, pancakes and hash browns.

"Any time I try to start a diet, eat healthy, any of that, my sister always has to bring in her f---ing fattening foods. And this has been going on throughout my whole life, and I feel like if I don't put my foot down and do something right now to change it, it's going to continue to go on and I will fail," Cross said in an interview.

"I'm an addict, and an addict can't have [a] little treat here, a little treat there. It has to be cold turkey," she added. "Jakie is skinny. She can eat biscuits, she can eat fried food, she can eat chocolate, she can eat anything. She don't gain any weight. I eat it, I look at it, and I'm gaining the weight."

And prior to moving out of her house, Cross told Jakie that she needs to respect her weight loss efforts.

"Right now I'm asking you: stop bringing fattening foods in the house. Stop bringing anything unhealthy in the house. Stop," she said. "You're killing me."

1,000-Lb. Best Friends airs Mondays at 10pm ET/PT on TLC and discovery+.