Oh my, I have the same problem, Brandon. (my name is Brandon, too
) I'll play things perfectly by myself, but when I play in front of friends my performance isn't as good. And when I'm in guitar shops I feel so self-conscience. I feel okay when there are others in there jamming, but when they leave and I'm jamming alone I'm like,
"oh crap, i'm soloing...." I just play stuff I know pretty well, and I don't go for the stuff that's hard.
I once heard a guy say to the guitar shop clerk that he didn't like to play in front of people; he felt like people were judging him. The clerk said don't worry about, he used to feel the same way; just jam. So, my advice is just get used to playing the easy stuff in front of people, and don't go for the stuff that you know you will mess up on for sure. This way you will have less pressure on you because you know the piece so well. And when the inevitable time comes that you mess up, don't let people know you did. (it always comes for me) Just keep jamming. I'm fond of letting people know what I messed up on after they complimented me. They didn't even know I messed up most of the time, so I try to stop that.
(I even have webcam stage fright when I'm broadcasting on ustream.tv)