Kate Gosselin isn't holding anything back.

The reality star is opening up about her very public divorce with Jon Gosselin, and how her ex-husband blindsided her after his attitude mysteriously changed in the time leading up to their split.

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"I really would have thought he'd have been here for the long haul," Kate told People. "The weirdest thing is that overnight he became a different person."

Further, Kate revealed Jon began to stay out late and was spending much of his money on motorcycles and cars, despite having to support his eight children.

kate gosselin kids

"People closest to me thought I was crazy and making it up," Kate continued. "When they saw it for themselves, they were like, 'Whoa.' They saw the proof — and then I saw all the letters from women saying, 'I've been there, too.'"

During the same interview, Kate heartbreakingly revealed her son Collin was currently away at a program to treat his special needs. Moreover, 15-year-old twin daughters Mady and Cara opened about their increasingly strained relationship with their estranged father, to which he recently responded to.