Just before boarding Roger's seat assignment was changed. He was moved to a middle seat 7 rows ahead. I was left between a VERY UNFRIENDLY married couple that did not want to talk-to each other or to me. They refused to sit together and he was coughing a lot before the plane was even loaded to fly! I asked the flight attendants for help. TWO WOMEN ATTENDENTS WERE GREAT HELP. We managed to sit together close to the rear of the plane. It would have been a dreadful 11.5 hours between those two people ROW 26 I and K. In 55 years of flying that would have been my worst experience.