YOU SAID:
He was my best friend, My one and only.
INTO JAPANESE
彼は私の親友であり、私の唯一無二の友人でした。
BACK INTO ENGLISH
He was my best friend and my only friend.
INTO JAPANESE
彼は私の親友であり、唯一の友達でした。
BACK INTO ENGLISH
He was my best friend and my only friend.
You've done this before, haven't you.