yay i didnt think i would get the first answer, i think you should go - well at least pop in see if theres anyone you know or anyone you could strike up a conversation with, and if not then come home.
Well I've walked into many a pub on my own, but I know that I will see at least one person I know....difficult one, if you are an outgoing type then you will probably not find it a problem. Take a book, order a drink sit not too far from the madding crowd, and have the consolation that if nobody does start to talk to you, you won't lose face because your enjoying your drink and reading a good book!!
I always read in pubs and don't mind being by myself in the least, but to them it might seem a bit odd, a girl by herself...they always assume you're there for "something" ! lol
anyway, off I go. Don't do anything I wouldn't do while I'm gone....