I agree. It really doesn't sound as if you're best friends anyway, just that you don't want to be rude. And I understand you being ticked about not about the change of plans. (it's a running joke in my family that I'm always the last to know anything; a joke to them, but not funny to me at all)IMO I'd tell her that because you were not notified till the last min and you have plans for that day, you cannot come
You're under no obligation to show up if you don't want to. Since you already had plans for that night, why not make an appearance then let the bride know you have a previous engagement and can't stay? I don't think I'd bother to tell her you don't like the idea of a stripper. After all, it's her party and if she wants to get plastered with a half naked man, that's her call