Dean McDermott
Dean McDermott said sex with Tori Spelling "wasn't fantastic" on their Lifetime reality show "True Tori." Lifetime

Dean McDermott revealed on a clip for “True Tori” that his worst fear was cheating on his wife, but Tori Spelling questioned whether it was getting caught after he cheated. McDermott, who had an affair while he was shooting “Chopped Canada,” said he was unsatisfied with their sex life. His problems eventually led him to rehab in January.

"We had a great relationship and we had a great sex life,” said Spelling, 40, at the beginning of the therapy session. But McDermott, 47, clearly didn’t see it that way.

"We would have sex once every two weeks," McDermott said during an April 9 therapy session. "It wasn't fantastic." Spelling objects and raises her arms in the air as if she’s ready to give up. McDermott appears clueless and asks what he said wrong.

[Click here to watch the clip, courtesy of People.com]

The counselor explains, "Dean, your expectations of what a marriage is supposed to be sexually, it's like a fairy tale.”

McDermott and Spelling were married in 2006 after they met on a movie set and left their respective spouses. The couple has four children together: Liam, 7; Stella, 5; Hattie, 2; and Finn, 20 months.

The two have appeared together on reality shows such as “Tori & Dean: Inn Love” and “Tori & Dean: Home Sweet Hollywood.” But “True Tori,” which premieres on Lifetime Tuesday night, has a more somber tone. The new program will reveal McDermott’s betrayal and how it affected his wife.

"I'm insatiable," McDermott admits in the clip. "Sex was an escape, just like drugs and alcohol."

"But I don't understand, like why her?" Spelling tries to understand.

"I wasn't attracted to her," McDermott says. "It was just like a warm body."

As if things couldn’t get any worse, McDermott gives a heartbreaking answer to one of Spelling’s questions. As previously seen, the celebrity chef says: "I cheated on my wife. That's my worst nightmare."

But then Spelling asks, “Or that you got caught?" McDermott is at a loss for words before he finally utters, “I don’t know.”

“True Tori” will air on Lifetime Tuesday at 10/9c.

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