DEAR ABBY: My best friend and I are middle-aged women. Throughout our long friendship, I have been one of the few people in her life who was there for her as she dealt with boyfriend problems, elderly parents, serious illnesses, deaths, etc. She became engaged for the first time recently, and asked me to go out of town with her to check out a potential wedding venue. While we were there, she looked away (wouldn’t even look me in the eye) and announced that only her sister (with whom she doesn’t get along) would be in her wedding party. Although ...