I think everything apart from "cardinal" is right. It doesn't sound like "cardinal", although it does start with a "k" sound. "But I wanted only keep my love" is good enough for me, the message is clear enough.
Although it would be great for the lyrics to be in perfect English, but at least we know that she wrote it herself and is true to herself. Even if she just asked someone to check, someone might start accusing her of not writing her own lyrics. I think the reason why she didn't publish the lyrics is that she doesn't consider them as lyrics at all, it's like something she just sings along to in the end. Therefore I don't think it matters what she sings, although it's great to know that even the chorus's lyrics has such deep meaning.
We shouldn't really worry about the tiny details. I think the lyric's meaning is far more important than the grammar or whatever.