Gay advice/ help needed please!!?

I have been dating one of my friends, also a girl for the past year. First it was a secret because i didnt want anyone to know n judge but she was very ready n hated lying. It got very hard so we told a couple of friends. Now a few people know mayb about 10 or 15. We are going to a lesbian function with some of her friends who are gay but i dont know them that well. She wants to go as a couple but i am scared of telling them n what they will think, who they will tell etc. I don't want to care what they think and who they will tell, i want to be honest without it affecting me. im just scared n dont know what to do. some1 tell me what to do argh! Thanks