So I went on this date with this girl. Didn't close and kind forgot about it

Out of the blue, she invited me to her birthday party said I could bring a friend.

Here's the problem: I don't have any friends to bring to with me and I'm worried that by going alone I'll be seen as really low value (because I only know her and I'm not great at social situations).

But I don't get invited to that many parties so it'd be nice to get out and practice being social.

In my experience going to girls parties alone never works in my favor (in terms of getting laid).

Do you have any ideas how I can spin this into a potential good time?