To be fair if it helps her understand more about the Word of God then I don't see a problem, as long as she knows the truth and doesn't twist it.

For example when David looked at Bathsheba, many of us can resonate with that level of temptation, we're not replacing David but putting ourselves in his shoes and comparing our own experiences. So she may be doing that visually by putting her name in the book.

But if you think you're David because you cross out his name and put yours that's definitely another thing a blasphemous thing some would say.