Melissa Etheridge, who split bitterly with wife Tammy Etheridge a year ago, is now dating Nurse Jackie creator Linda Wallem.
"Melissa and Linda have been best friends for over 10 years," a pal tells PEOPLE, adding that Wallem served as Etheridge's "best man" at her 2003 wedding to Tammy. "They got together three months after Melissa and Tammy broke up."
Etheridge and Wallem, who share the same birthday (both turn 50 in May), attended the Emmys together last August. Today, Etheridge and Wallem "are in a committed relationship. They're happy," says the pal.
And, adds the source, Melissa and Tammy's breakup has grown less contentious since last summer's legal clash over finances and custody of their 4-year-old twins Johnnie Rose and Miller: "Everybody really is in a better place now."