scared to tell my mum I believe differently?

I come from a Roman Catholic Christian family. And we all believe in God (however my brother is questioning) due to the area we live in and the schools we went to I knew very little about other denominations par my own. 
Last year we started doing our GCSE religious and I realised I actually don't believe in a lot of RC believes and in more of a prosadant. 
The problem is no one in my family likes them. They all dislike prosadant sand especially dislike them during the orange day parade in a near by town. 
I know she'll love me no matter what as proven by past events but I still feel like I can't tell her I don't feel like a RC.