Selena Gomez's Rocky Year

Dec. 23, 2013— -- intro: It's been a roller coaster of a year for Selena Gomez, and it seems the 21-year-old singer and actress is ready for a break.

After announcing plans last week to cancel her Australian tour next year, Gomez has been enjoying some downtime. Seen cuddling a baby -- possibly her little sister -- in a photo she posted on Instagram, the pop star wrote, "I'm the happiest I've been in a while ... so blessed and thankful for the future, for release and to finally be happy for those I loved."

In another photo she posted Sunday, the singer appears pensive as she stares out a window.

Last Thursday, Gomez announced the cancellation of her tour dates in Australia and Asia after wrapping up her 55-show Stars Dance tour, saying she needed to focus on herself.

"My fans are so important to me, and I would never want to disappoint them," the former child star said in the statement. "But it has become clear to me and those close to me that after many years of putting my work first, I need to spend some time on myself in order to be the best person I can be."

Why now? A look back at Gomez's rocky year may offer some insight.

quicklist:title: Breakup With Biebertext: At the beginning of 2013, Gomez was still weathering her very public breakup from fellow teen pop star Justin Bieber. After two years of dating on and off, the couple called it quits at the end of 2012. But cuddly photos of the pair posted on Instagram by Bieber continued to spark speculation that they weren't quite finished. "He and I have had such a history together and I'll always care about him and protect him if anybody tries to be mean," Gomez told "Good Morning America" in July, while denying they were more than just friends.

quicklist:title: Turning 21text: Gomez also celebrated a huge birthday this year, her 21st, on July 22. For the big night, Gomez, was joined by 20 friends and family members, including her mother, her "Spring Breakers" co-star Ashley Benson and actress Francia Raisa, for a private dinner at the West Hollywood French bistro Bagatelle. Later, she mused about what it means to turn 21. "I've entered the decade of confusion about who I am and what I want to do with my life, and that's what this entire decade's going to be," she told Teen Vogue.

quicklist:title: Her Career Heats Uptext: The singer also got her best birthday present ever the same week when her debut solo album, "Stars Dance," shot straight to No. 1 on the charts and the single "Come and Get It" became her first to crack the Top 10. "I don't think I can celebrate any better than releasing my fourth album, having 'Come and Get It' and starting my tour," Gomez told "GMA" in July. "It's been crazy. ... I'm playing hard and working hard." Not only did she spend much of 2013 on tour, but the former Disney star also appeared in the movies "Spring Breakers" and "Getaway." "I feel like the moment I'm not working I get bored and then I go crazy. I'm going to keep going," she told "GMA"

quicklist:title: The Anti-Mileytext: While on tour, Gomez made headlines when she stopped one of her recent concerts to deliver a speech on what's sexy that could have been targeted right at a twerking, naked headline-grabbing Miley Cyrus, another former child star. "I get it all day, every day, that I'm not sexy enough," Gomez told fans at a concert in October during her "Stars Dance" tour. "Let me tell you one thing: The sexiest thing, I think, actually, I know, is class, and that's it."

quicklist:title: Jingle Ball Meltdowntext: Gomez is not perfect, however, and by December's Jingle Ball, the singer lost it when her audio and mic malfunctioned while she was on stage. Gomez dropped the F-bomb and later walked off the stage before finishing her set, according to Us Weekly. "Sorry, the sound isn't working!" Gomez was heard yelling to the crowd. "Are you guys having a good night? I promise, a lot cooler people are gonna come out tonight. Is it OK if I perform two more songs and you guys can get to it?" But she only performed "Come and Get It" before leaving the stage and deciding later this month that she needed a break.media: 21311083