My Mom is wonderful. She is a devout Christian, knows my beliefs and never ever pushes it on me. She supports me in everything.
I like to say my mom is a Christian but she's not a bitch about it. She has never used her religious beliefs as a hate tool and she accepts my non-belief.
You're lucky. My dad has become a brainwashed right wing methodist and worries that I won't see him again on the other side of the rainbow bridge...
You're very fortunate in that your mom is awesome and still here. Give her a hug today and thank her for being a fabulous mom. And seriously, you might think you tell her, and she "knows" what you think, but having you say it will make her day.