Regarding the Halloween party, the LW seems to have very little idea what parties are about. She's afraid the other guest might be uncomforable? What could possibly be uncomfortable about a grandparent being at this party? (That's the sort of lame excuse you come up with after you've overanalyzed things for hours.) Parties are supposed to be fun, yet she's intent on being uptight and inflexible. If she can't handle an easy request like this, she probably shouldn't be hosting a party to begin with.