Most of the time, people eventually see each others' points. Getting to that stage, however, is often a painful process.
Like Nam said, it's a dysfunctional family. It's like Thanksgiving, when Uncle George comes right out and tells Aunt Rita that she looks like a whore with all that makeup on, and to stop dressing like she's 23, for God's sake, because she's 52 and time hasn't been kind.
Granted, it's a bit rude, but everyone else was thinking it. This of course leads to about 3 hours of old laundry being brought up, Aunt Rita throws Uncle George's toupee into the garbage disposal, the kids sit around fascinated, Grandma has to lay down, Grandpa threatens to stab Uncle Marty because he yelled at Grandma, and Robert goes outside to wonder why the hell he invited all these people to his house.
After the three hours have passed, someone says something that makes one person laugh, and everyone's back to being a family again.
Until Christmas.