How do I get over this? [read details]?

Um.. well, it’s not exactly a fear.
I play the guitar and sing, but when there’s other people in the room, everything I know, everything I can do.. I just lose it and can’t sing/can’t play well. I tried to sing to my boyfriend today and I almost had a panic attack. I mean, come on! How can I get over this? I want to become a musician/singer and I won’t be able to do that if I lose my voice/start feeling dizzy/want to cry each time…

Help, please..