The American Idol winner, 24, tells Cosmopolitan in its May issue that she's shy and "horrible around guys" – and hasn't had a serious relationship since she split with college boyfriend Drake Clark in 2005.
And her newfound fame hasn't helped.
"Guys who would never look at me twice before might ask me out now, so I guess I have better opportunities," she says. "But when I do meet a guy, there's this 'Does he just want his picture in a magazine?' factor."
Still, she's optimistic. "I'm not saying I want to get married tomorrow, but I'd like to have someone other than my mom to call when I have good news."
Underwood has been spotted recently with British singer Oliver Trevena, Cosmo notes, but she denies she ever dated fellow Idol contestant Anthony Federov or Dallas Cowboys quarterback Tony Romo.
(She was linked with Romo after she was seen at a Cowboys game on Christmas, but Romo himself told reporters: "We're friends. She's a very nice, sweet girl, I care for her and whoever ends up with her will be a very lucky guy.")
Besides the guy issue, Underwood says there's another downside to fame: "The music business is about packaging. People have to be pleased by what they see on TV or they'll change the channel."
But she says she doesn't diet. "I gained weight on Idol, but I didn't starve myself afterward," she says. "I may think about it a little too much. I might feel guilty if I eat a pizza. But I've tried to be healthy and exercise as much as I can. If that's made me lose weight, I guess I needed to."