Reddit mentions of Irreligion: A Mathematician Explains Why the Arguments for God Just Don't Add Up

I have no experience in this regard, but somehow I don't think handing over a thick book is going to help her much. Something smaller, some pamphlets or talking points that can quickly summarize the main points of atheism that she can skim back and forth over may be better.

I recently borrowed this book from the library, it's an incredibly short and small book with short chapters explaining the fallacy behind common religious "logic."

Also, this pdf that was posted here some weeks ago; has very short, succinct arguments about theistic positions and why they're fallacious.