Selena Gomez attends the 22nd annual Glamour Women of the Year Awards at Carnegie Hall on November 12, 2012 in New York City. Credit: Theo Wargo/WireImage for Glamour Magazine

Beautiful after breakup!

Selena Gomez showed Justin Bieber what he was missing when she stepped out for her first official public appearance since splitting with the "Boyfriend" singer on Halloween.

The newly single star, 20, has kept a low profile in recent days but was all smiles as she walked the red carpet at Glamour's Woman of the Year Awards at Carnegie Hall in NYC on Nov. 12. Wearing a white Giambattista Valli dress with a deep V-neck and matching pumps, the magazine's December cover girl struck a sassy, lighthearted pose for the cameras.

"Selena broke up with Justin about a week ago. It's been a really challenging experience over the last year because of their crazy schedules," an insider told Us Weekly on Nov. 9, shortly after E! first reported that the couple of nearly two years had gone their separate ways. "Selena definitely had some major trust issues with Justin." See more photos of Selena Gomez in NYC.

Indeed, the two encountered their share of ups and downs. After taking their romance public in February 2011 at the Vanity Fair Oscar party, Gomez faced backlash from her superstar beau's adoring fans on the Internet. The couple also dealt with breakup rumors several times throughout their courtship.

"They are [young] changes from day to day," the source explained. "Right now it is a break and tomorrow it could be back on knowing's hard to say how they will end up. Maybe she feels more serious about it this time. We'll see."