Answer: confidante
AnswerCrossword Clue
CONFIDANTEGirl BFF, more formally
CONFIDANTEClose friend, perhaps.
CONFIDANTESecret sharer
confidante(French) a (female) person confided in or entrusted with secrets, esp in love affairs
confidantesofa or settee, esp. of the 18th century, having a triangular seat at each end divided from the greater part of the seat by an armrest
confidantewoman to whom secrets are confided or with whom private matters and problems are discussed