YOU SAID:
I lost my heart because you broke it.
INTO JAPANESE
あなたがそれを壊したので、私は心を失った。
BACK INTO ENGLISH
I broke my heart as you broke it.
INTO JAPANESE
私はあなたがそれを破ったときに私の心を壊した。
BACK INTO ENGLISH
I broke my heart when you broke it.
INTO JAPANESE
私はあなたがそれを壊したときに私の心を壊した。
BACK INTO ENGLISH
I broke my heart when you broke it.
That didn't even make that much sense in English.