Katherine Heigl talks new thriller 'Unforgettable,' overcoming 'mommy guilt'

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WATCH Katherine Heigl talks new thriller 'Unforgettable,' overcoming 'mommy guilt'

Viewers will see a new side of Katherine Heigl in the upcoming thriller "Unforgettable."

The 38-year-old actress plays an unhinged ex-wife who has it in for her ex's new fiancé, played by Rosario Dawson.

"It was fun," Heigl said on “Good Morning America” of her villainess character. "I know that sounds very strange, but there's a weird freedom to playing a woman who really is not a people pleaser, who is not trying to make other people happy and who is not bending over backwards for other people's needs and it is all about...what she wants."

Heigl, a mom of three, said it's been a "whirlwind year" amidst filming and welcoming her son, Joshua, in December.

"Right now it's especially complicated because the girls are in school, so they're staying home but the baby needs me to eat, survive, so he comes with me," Heigl said with a laugh. "I think with every mother it's just this sort of perpetual mommy guilt that somehow you're kind of not nailing it and to mess up his schedule...because of me, my work needs, feels a little selfish. But honestly, I'm going to smack myself and get over that because I'm doing my very best."

At home, Heigl said her musician husband, Josh Kelley, has a little fun embarrassing her and the kids.

"He plans it out, it's amazing," she said. "My niece lives with us and she's a freshman in high school so he has to drive her. He puts on my pink robe, he gets his cup of coffee and he drives her down to the bus stop and then he gets out of the car to wave her off in his pink robe."

"Unforgettable" hits theaters Friday.