I'm with Paula. I have 3 children. 2 with Aspergers and one with severe anxiety and they all struggle socially. It's something that I struggle with too - I've never been in with the popular kids or adults, like you it's easier to sit on my own rather than try to join in with people. However, I've started to try to push myself and push my girls to push themselves to do simple things like order a drink or go out and ask a question..... It's small changes and challenges and I'm hoping it builds up...
But my girls are happy to be who they are in their own bubbles and if people don't like it then they aren't worth bothering with!