Mary J. Blige has warned her husband to stay away from any female friends, because she doesn't think men and women can just be pals.

Blige and her record producer partner Kendu Isaacs will celebrate their 11th wedding anniversary next month (Dec14), and the singer insists one of the things that has kept their marriage on track is a rule about friends.

The Family Affair singer explains, "All females for me, all guys for him.

"There's none of that, 'Oh, that's my female friend', or, 'Oh, that's my guy friend...' No, not in a marriage. I've never seen that work."