It's been a hellish week for Anna Duggar.
On Aug. 20, her purported ultra-conservative Christian husband Josh Duggar admitted to cheating on her and having an addiction to pornography. Now, his parents, former 19 Kids and Counting stars Jim Bob and Michelle, have announced that he's entered a long-term rehabilitation program, leaving Anna and their four young kids to weather this maelstrom without him.
For this week's cover story, a source close to Anna gave PEOPLE exclusive insight into what Josh's embattled wife is really like.
Growing up as one of eight children to parents Mike and Suzette Keller, Anna had a strict, religious childhood similar to that of the Duggars. "Her parents are even a little more extreme," the source told PEOPLE of the Kellers.
"Anna and her siblings were always taught that if you follow these 10 steps or whatever, God would bless you."
When Anna, now 27, met Josh at a Christian homeschooling convention back in 2006 when she was a teen, she wasn't allowed to gush about him to her siblings. "That's not something that's shared amongst siblings," says the source. "They always got 15-minute, one-on-one sessions with their mom every week. That was the time to share their feelings, but other than that they had to keep their feelings to themselves."
Anna was particularly close to her youngest sister Susanna. "Growing up, they were attached at the hip," says the source. "They did everything together."
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Despite her rigid upbringing, Anna still had spunk. Says the source, "She's really fun. She was always the bossy sister, but in a fun way. If she and her siblings were playing a game, she would make sure they were doing it exactly by the rules. They always had a good time together."
Now, a source close to Josh's family says Anna is isolated and has changed drastically. "Ever since she met [the Duggars] she has acted more like Michelle," says the other source. "She talks like her, real soft. She, like, whispers."
RELATED: Anna Duggar's Isolated Life: She Feels It Is 'Not Godly' to Get Mad at Josh
While some of her siblings have been outspoken about wanting her to leave Josh, the source close to Anna says that thanks to the brand of patriarchal Christianity that her in-laws and parents prescribe to, divorce is highly unlikely.
"I don't think her parents ever thought they would ever come to a situation like this," says the source, revealing that Anna's sister Rebecca is going through her own divorce right now. "They just don't know what to do," the source says of Anna's parents. "They always taught their kids that divorce was never an option. They never even thought about cheating. But that's not how life works."
For much more on the fallout from Josh Duggar's secret double life and the Duggars' ultra-conservative lifestyle exposed, pick up this week's issue of PEOPLE on stands Friday