Solange Knowles revealed that she is struggling to find a work-life balance and "devastated" to announce that she has cancelled her European tour dates for August 2013.

The singer told fans that it was the "best decision for my mental/physical health."

"I wish I could put in words how much of a difficult decision this was," the singer, wrote on her web site, "but between moving part time to a new city, starting my son in a new school, and writing/recording my new record ... I really had to make the best decision for my mental/physical health and provide some stability for my family."

Beyonce's baby sister recently made the move to New York from Los Angeles with her son Daniel Julez, 8. She is also working on her third solo album.

"I am so so sooooo sorry if I've disappointed ... and really hope to make it out to those special cities soon enough!" she said.

Days earlier, Solange stepped out for the New York premiere of the latest Woody Allen movie Blue Jasmine. She showed no signs of fatigue.

Dressed in a mint-colored mini skirt, she walked the red carpet with boyfriend Alan Ferguson at the Museum of Modern Art. She teamed her outfit with pale pink ribbon style heels, chunky earrings and a beaded bag. (See photos.)

Last week, she attended a rally Borough Hall in New York to express her outrage after George Zimmerman was acquitted for the death of teenager Trayvon Martin.

"Seeing & gathering with people today/tonight all for the same fight helped to restore my faith in humanity...," Solange tweeted after the rally.

"Thank you to everyone who came out to support #Bklyn4trayvon rally! This was just a start to a long journey of Justice and Equality!" she wrote.

Tags: Solange Knowles Beyonce