Fergie says it’s not easy to stay slim — especially after gaining 17 pounds to star in musical Nine.
"I'm not going to lie: There are times I play mind tricks on myself, like that the french fries are poison," she admits in the May issue of Elle magazine (on stands April 14). "With desserts, I'll let myself have just one bite, but I'll look like a freak when I'm eating it, like when I did Duncan Hines commercials as a kid, just savoring every morsel."
PHOTOS: See what Fergie -- and other stars -- are wearing this spring
When she's mocked for her looks, Fergie, 32, takes it personally.
"It has hurt me in the past when people say things like how 'fugly' I am or how horrible I look," she says. "I've had to learn not to give it such a high priority in life... Look, when you're trying to juggle all of this in your life, sometimes you're not going to look perfect. I don't have time to get a facial every couple of days."
PHOTOS: Stars who love their bodies
It was her husband Josh Duhamel who faced infidelity rumors late last year, Fergie admits she wasn't always so faithful.
PHOTOS: Shocking stripper scandals
"When I was younger, I used to be the cheater. I'm not talking about going all the way—I wasn't doing that in high school! But I'd have boyfriends, and then spring break would come around and I'd be a little bit naughty."
"I'm a relationship girl, a romantic," says the singer-actress, who wed Duhamel in January 2009.