The star, whose full name is Usher Raymond IV, filed divorce papers with the Superior Court in Atlanta, Georgia.

The 30-year-old Grammy winner and his wife, 38, married in August 2007. The couple have two sons together, Usher Raymond V, 18 months, and Naviyd, 6 months.

“A lot of that is because Usher has been in Vegas recording his new record. He’s done his best to keep Tameka away,” a source tells PEOPLE.

Tameka, on the other hand, is not willing to give up on their marriage. “She’s been in his life for so long. She’s very loyal to him. Tameka is the type of woman to stick it out,” the insider adds.

A hearing has been set for July 15.