YOU SAID:
i can not believe you would do that to my friend
INTO JAPANESE
私はあなたが私の友人にそれをするだろうと信じることはできません
BACK INTO ENGLISH
I can not believe you will do it to my friends
INTO JAPANESE
私はあなたが私の友人にそれをするとは信じられない
BACK INTO ENGLISH
I can not believe that you will do it to my friends
INTO JAPANESE
私はあなたが私の友人にそれをするとは信じられない
BACK INTO ENGLISH
I can not believe that you will do it to my friends
That didn't even make that much sense in English.