Anxiety taking a seat at the wheel

Gr. I hate my Generalized Anxiety and Social Anxiety problems...thats why i love the internet..i've been feelin anxious all day thinking about the upcoming event on sunday, I meet my husband's new girlfriend. What will she think of me?
Wait a mintue? why do i care? I dunno..but i do. I want to be nice to them, but will i? I don't know how i'm going to act and thats enough to bring on an anxiety attack in and of itself.