JUST SAY NO! That’s how several of my relatives are handling Thanksgiving invitations to share a turkey dinner this year. My brother, Billy, would love to sit down with his son’s family and his grandchildren, but he has RSVP’d a definite “No.” His son’s mother-in-law in Houston is cooking the big dinner with all the trimmings and expects her family to show up. My cousin’s wife, Lesa, encountered…