Why am not able to relax and be myself around new people?

I feel like I need to impress everyone around me to make them like me. There are days that I simply don't talk to anyone. I'm tired of feeling this way. I'm getting lonely and sometimes feel like getting help from a counselor or someone, but for some reason I end up telling myself that I can deal with it myself. I believe that this is due to a subconscious fear of being judged by the counselor/therapist.