You tell us you are quite the "chicken" about talking to your girlfriend. Please realize that this isn't all about you, but about your relationship. This keeping your secret to yourself affects how you relate on a daily basis with your girlfriend.
If she were to keep a similar secret from you I think you would notice she was keeping her distance from you and it would affect how you felt toward her. You can let her know that you are fearful of how this information will affect her and your relationship but that you realize it is more important that she knows. Please don't let your fears get in the way of becoming closer with her.
Karan
