Katherine Heigl Reveals Why She'll Never Cheat on Husband

Don't expect to catch Katherine Heigl in a torrid affair with another man!

In the actress's latest iVillage blog post, the 33-year-old "One for the Money" star says she's never been tempted to cheat on her husband of four years, singer Josh Kelley, 31.

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"I have no desire to physically hook up with any man other than my husband and have been a serial monogamist from the moment of my first serious relationship at 20," Heigl writes. "I have never been able to connect with a man sexually without it becoming emotional, without giving a piece of my heart and soul to that connection."

The actress and mom to Naleigh, 3, says she's "always loved the idea of Samantha on 'Sex and the City,' but it just isn't how I'm built."

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"I understand that every human being on earth wonders if the grass might be greener in other pastures, but I could never imagine myself really going there or really wanting to," Heigl explains. "I guess the relationship I'm in is so consuming that the idea of a dalliance with another man sounds exhausting."

"It's hard enough to make one connection work," she writes. "I can't imagine, even for four days, splitting myself between two!"

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Heigl admits that her marriage isn't perfect, but they "stand by each other" and "respect each other's thoughts, ideas, passions and fears."

"We've had some pretty explosive fights over the years trying to make our marriage work, but it's been worth it," Heigl adds. "I do not want to live my life without Josh in it and will do everything I can to make sure I don't have to -- except give him the freedom to don a costume and mask and bang some other chick."

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