"I was like, ‘Something just isn't right. She would have called somebody,’” her mom told INSIDE EDITION.
Crystal's Chevy was found abandoned with a flat tire at the side of the Blue Grass Parkway outside Louisville, Kentucky. Her purse and cellphone were still inside.
Crystal's boyfriend, Brooks Houck says he woke up July 4 to find her gone from the home they and their two-year-old son share near Louisville.
Police have not named any suspects and say the boyfriend is being "extremely cooperative."
But Crystal's parents and other family members are suspicious.
“Why would my daughter leave in the middle of the night?” asked Crystal's mom.
They say Houck has not taken part in the search they've been organizing every day since Crystal disappeared.
“I'm not accusing him of anything, I'm just saying, I don't think he's being totally honest about everything,” said Crystal's mom.
Crystal's mom described the moment she told Houck she was going to file a missing-persons report about her daughter.
“He looked at me as calm as he could be and said, ‘I think that's what you should do.’ He never once said, ‘Would you like me to go with you? I'm concerned, too,’” she said.
Houck - who owns a construction business and ran for local sheriff last year - called in to Nancy Grace.
He said he and Crystal had "a stressed-relationship at times." But he insisted he had nothing to do with her disappearance.
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“I'm 100 percent completely innocent in this,” he told Grace.
“Some people have accused you of not being involved enough in the search efforts. What's your response?” asked Grace.
“All of my efforts in searching for her have been done behind-the-scenes,” he said.
Searchers are braving 90-degree weather. Emotions are running high as they come up empty-handed.
Crystal's sister, Brooke, had to be consoled by their mother.
As bloodhounds and searchers scour the woods, Crystal's distraught parents have a message for their missing daughter.
“We love you. We're not gonna give up looking for you,” said her mom.
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