How to tell my parent's that I don't want to be religious?

I'm turning eighteen in about six months, and my parents still have a manipulative behavior with me. I really do love them, and I have followed their rules all of these years and acted complacent, but I don't feel like I have to pretend to be religious. They've literally sent me to christian school, banned me from listening to secular music, taught me that homosexuals were different, and that the only way to be happy was through christianity. I don't want to continue going to church and act like I actually agree with what is being said. I don't want to upset my mm, and make her feel unaccomplished (since she wanted me to be a devoted christian,) but I feel like it's time to develop my own beliefs. How do I tell her? Anything is appreciated. Thank you.

Read more: How to tell my parent's that I don't want to be religious?