Re: take a dog for a walk or for walks?
B could mean that she goes to more than one party every night.
B could mean the she goes to a different party every night. In other words, it could have the same meaning as A. But anyone who would go to a party every single night might well go to many parties every night, so I don't know which is mean.
A would never be assumed by a native speaker to mean that she goes to the same party, night after night. It's not logical. We all have knowledge of the real world and need to use it to understand the sense of what someone says.
A sounds like she goes to the same party every night
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.