The Torment of Socialization

I am most comfortable when I am all by myself. When I am with family (outside of my husband and daughter) or a small group of friends, I am at a 3 or 4 on the Freak Out Scale. (10 would be 'OMFG, I can't deal. I'll be hiding under my bed. Thx.') I can smile and bear it but the inner monologue is rumbling on.

'What if I say something wrong?'
'Is that joke funny? Am I the only one who thinks it's funny?'
'Everyone thinks I'm an idiot. Sure, I'm answering a lot of these trivia questions but that doesn't make me SMART.' (My family plays a lot of board games together.)
'They're still holding a grudge for that minor kerfluffle that happened 10 years ago.' (My 'reality' sensor knows that this isn't the case and those involved have probably forgotten all about it. I don't forget.)

And this is when I'm with my family. Throw in some strangers and that anxiety level steadily rises.

There are two events happening this weekend. Both are high-anxiety level events. Luckily, I can only attend one. Two might make my brain explode.

The attended event is a birthday party for one of my daughter's friends. I have no idea who will be there, which is a mental killer to begin with. Add in the fact that the party is taking place at an arcade-type area where I am not comfortable just dropping my daughter off. I know that I will be expected to chat with the moms while the kids play.  Anxiety Level? 5 to 6

The event I will not be attending is a mix of a rehearsal dinner, bachelor party, and bachelorette party for my husband's best friend and his soon-to-be wife. Thanks to Facebook, I have a good idea of the guests at this party. However, these are all people that are my husband's college friends. While they are kind and accepting people, I do not count them as my friends. We're just very different types of people. As a result, I tend to feel uncomfortable around them. By no fault of theirs, trust me. It is all in my head. Anxiety level? 5 to 6

I'm not really sure if it is possible to fix this problem. After all, it's not like I have a breakdown every time a new social situation comes up. I am capable of smiling and pretending things are OK. However, every time words leave my mouth, I am worried that someone thinks what I am saying is dumb or ignorant. As a result, I frequently just say nothing.