Along with Criscilla's ongoing cancer fight, the country singer and his wife both tested positive for COVID-19 recently

The odds haven't always been in Coffey and Criscilla Anderson's favor.

As Criscilla continues to fight stage 4 colon cancer and Coffey works on his career as an independent artist, the stars of Netflix's Country Ever After have long had to endure their fair share of bad news and dire predictions. But back in October, as Criscilla's doctor touted the possible benefits of a new clinical trial involving an immunotherapy treatment for her cancer, the couple looked at all the odds involved and made a decision: it was worth the risk.

"I had been so healthy," Criscilla, 40, tells PEOPLE from their California home. "I had been taking my supplements and natural treatments and my diet was on point. I would be taking three drugs as part of clinical trial, and my doctor had already seen great results with it."

"He told me that there was one in 10 chance I would get a rash and 1 in 20 chance that my liver would get inflamed. And I was like, 'I'd be good,'" she added. But she wasn't.

"I took my first round [of the treatment] and I turn out to be the 1 in 20 with the inflamed liver and the 1 in 10 with one of the most extreme rashes my doctor had ever seen — and all of this was at the same time as the show was premiering," remembers Criscilla, who was originally diagnosed with cancer in 2018. "It should have been my happiest of days, and instead I was praying to God I would make it another day."

"Criscilla had a head-to-toe rash that itched for 15 straight days and a liver that was sick," adds Coffey, 41. "I was worried because she just couldn't get any relief."

Criscilla would end up spending nearly a week in the hospital while Coffey handled an onslaught of attention via the success of their Netflix reality show. But soon, she says her physical and mental energy started to deplete. Coffey knew deep down that there had to be somewhere else where his wife could recover.

"After four days in a khaki-colored room with white walls surrounding you, you can go crazy," Coffey remembers of his wife's plight. "There is no music, people are sick, everyone has masks on, you can't see anyone, you are sitting in the same bed sick every single day. So Criscilla was like, 'I have to get out of here.'"

So Coffey took her home to recover alongside not only him, but their children: 8-year-old Ethan, 6-year-old Emmarie and 3-year-old Everleigh.

"Basically, she said, 'If I'm going to fight this thing, I'm going to fight this thing with my babies by my side," remembers Coffey, whose song, "Mr. Red White & Blue" went viral on TikTok back in July. "She would say, 'I get strength from being around you all. I'm not getting any better in here.' We had her discharged in an hour."

Coffey Anderson
Coffey and Criscilla Anderson
| Credit: Netflix

And if stories always had happy endings, this would be where Criscilla and Coffey would bask in a time of healing and a much-needed return to normalcy. But that didn't happen — instead, they both contracted COVID-19.

"We made it through, but it was hard," admits Criscilla of their shared battle with the coronavirus. "It was definitely different. I felt like I was becoming a burden to Coffey and to everyone that was coming to help, and I was getting tired of that."

"It has been a hard 45 days. I'm not going to lie," she added.

Criscilla — who has used everything from high-dose vitamin C treatments to time in barometric chamber, infrared saunas to following a strict vegan and ketogenic diet to treat her cancer — admitted that she started to get frustrated and lose hope.

"I don't want to say that I am losing hope, but there's only so much a person can handle when it comes to one's health," she says, "You just get to a point where you are tired, and you feel defeated."

But that is usually the moment when Criscilla, via a mix of determination and faith, finds a way to focus on the positive. And the positive right now is that her cancer scans are looking better, with her tumors either staying the same size or even shrinking.

"Those scans give me a lot of hope that I am going to be able to enjoy the holidays," Criscilla says. "I mean, that's what cancer is. It's a wave of emotions. Every time you go into the hospital, you want to hope for the best but at the same time, you have to mentally prepare for the worst. And when you are preparing for the worst, you have to know that that is the journey of cancer."

"There are ups and there are downs, there are the good scans and there are the bad scans — that is just the journey of cancer," she added. "When you realize that, it's easier."