It ain't over 'til it's over!

Though Dr. Paul Nassif, 50, filed for legal separation from wife Adrienne Maloof, 50, on July 30, a source tells the new issue of Us Weekly (out now) that they're not quite ready to divorce.

"They are getting professional help and trying to save their marriage," the source explains. "But their relationship is very volatile. They are trying to do what's best for their kids."

In his filing, plastic surgeon Nassif asked for joint custody of his three sons, Gavin, 9, and twins Colin and Christian, 6. The couple's marital woes will play out during The Real Housewives of Beverly Hills' third season, airing this fall on Bravo.

For more details on the couple's surprise breakup, watch this week's Hot Stuff video, as explained by Us Weekly Senior Editor Ian Drew and special guest, My Family Recipe Rocks host Joey Fatone!

Also in the roundup: Bachelor host Chris Harrison flirts with "an attractive brunette" in Montauk, New York, new couple Ashton Kutcher and Mila Kunis vacation in Bali, and much more!