Wow, that is amazing she read CoC! That is very open minded of her.
It is weird isn't it to feel that you are truly now an orphan; doesn't matter how old we are. It took a long time for me to get over that. Probably because I looked after my own mom for sooo many years.
You were lucky to have such a good mom. They can instill so much in us with their mothering, in spite of the religious differences. Grieve and celebrate her as you wish. Remember you got to have her for almost your whole life, which is a gift. You were such a good son, and she knew it.