YOU SAID:
my fiance is getting married to my wife
INTO JAPANESE
私の婚約者は私の妻と結婚しています
BACK INTO ENGLISH
My fiancé is married to my wife
INTO JAPANESE
私の婚約者は私の妻と結婚しています
BACK INTO ENGLISH
My fiancé is married to my wife
You've done this before, haven't you.