YOU SAID:
you are the best thing that's ever been mine
INTO JAPANESE
あなたは今まで私の中で最高のものです
BACK INTO ENGLISH
you're the best thing i've ever had
INTO JAPANESE
あなたは私が今までで最高のものです
BACK INTO ENGLISH
you are the best i ever had
INTO JAPANESE
あなたは私が今まで持っていた最高です
BACK INTO ENGLISH
you are the best i ever had
You've done this before, haven't you.