Charles Ellicott Commentary Judges 14:20

"But Samson`s wife was [given] to his companion, whom he had used as his friend." — Judges 14:20 (ASV)

To his companion, whom he had treated as his friend — that is, to the head groomsman (the bride-conductor, Septuagint); “the friend of the bridegroom” (John 3:29). Hence, even if the suspicion regarding the meaning of Samson’s words in Judges 14:18 is unfounded, it is clear that there was treachery and secret hostility at work. Bunsen renders the phrase, “to his companion, whose friend (amica) she was.”