YOU SAID:
She was alone in this world, and she knew that she had to make the most of it.
INTO JAPANESE
彼女はこの世界で一人ぼっちであり、それを最大限に活用しなければならないことを知っていました。
BACK INTO ENGLISH
She knew she was alone in this world and had to make the most of it.
INTO JAPANESE
彼女は自分がこの世界で孤独であることを知っており、それを最大限に活用しなければなりませんでした。
BACK INTO ENGLISH
She knew she was alone in this world and had to make the most of it.
That didn't even make that much sense in English.