DEAR ABBY : I’ve been married to the same man for nearly 50 years. We raised a sweet family, had successful careers, and never strayed from each other. For the last 20-plus years, I’ve had little or no desire for sex. I understand it medically as well as emotionally, but Hubby doesn’t get it at all. He thinks we should be like we were back in the ’70s and ’80s.  I’m happy for senior couples who engage in healthy sexual relationships. I am just no longer into it and, honestly, also not