Social anxiety disorder?

I haven't been to the doctor for it cause I just think they will think I'm doing it just to get meds. I am 26 and EXTREMELY SHY. I don't have any friends. The only people I can actually talk to without getting nervous is my parent, siblings and my BF. Other than that I get very nervous and anxious talking to people. I feel it's ruining my life. My BF is on the verge of leaving me because I can't "open up". I've been with him 6 years. What can I do to help myself? The thought of therapy scares me cause I wouldn't even be able to talk to them. Any help? :(