Telling Secrets

Okay so my best friend and I have been friends for 4 or 5 years. We are both rather innocent girls but lately I've been trying to change that about myself and she isn't really into that. I've been talking to guys and do stuff with them, I'm still a virgin but just not as much as I used to be if that makes sense. I want to tell her what I've done and be honest with her but I don't know how she will take what I have to say. I just don't want the way she thinks of me to change because she's like a sister to me. I just don't know what to do😓