my girlfriend and i

So, i am a female and so is my girlfriend, clearly. My mom is a very intense christian woman & it’s not that she’s against it but she doesn’t approve of her children being in the lgbtq community. But it is her house her rules , so ya. My girlfriend knows about all of this and is trying to help me out But my dilemma is i can’t tell anyone about me and her because somehow it’ll get out to my mom. I just need guidance & to come clean to get but if I do , things will never be the same. I really have no idea what to do.