My late uncle was a widow. His deceased wife’s best friend was also widowed. The two couples had spent years together... dinners, vacations, etc.. So, you now had two widowed people who had common interests and been in each other’s lives for 30 years. They “secretly” moved in together. They kept it very, very quiet because they were afraid they would upset their adult children. Finally, my cousin came to him and said, “Dad, for the love of God.. please marry her. The grandchildren are talking. You aren’t setting a good example!” We lost both just a few years ago. Funny in a way because marriage 2 lasted longer.. both died close to 100 years of age.
It is called “Society Security Sin” meaning older couples would live together in order to keep their bennies.