Welcome to the forum Nnotsure.
I have not read any of her books but I have listened to some of her talks on religion years ago. I remember listening to her talk about her book,
The Case for God. It threw me off because I thought it was another defense of God's existence but it was more about history of religion.
Karen Armstrong is no longer part of any organized religion as far as I'm aware. She left Catholicism early on in her life. She would probably say that she is spiritual but not religious.