YOU SAID:
we could have saved her
INTO JAPANESE
私たちは彼女を救うことができた
BACK INTO ENGLISH
We were able to save her
INTO JAPANESE
彼女を救うことができました
BACK INTO ENGLISH
Was able to save her
INTO JAPANESE
彼女を救うことができた
BACK INTO ENGLISH
Was able to save her
That didn't even make that much sense in English.