"In my early 40s I decided to develop a spreadsheet of activities and interests I had (or was interested in learning) that would keep me physically fit, keep my brain active and provide me with the much needed social connections."
We like to trust people. That is a good thing. However, sometimes we can be taken advantage of if we are not careful. As we grow older this can become a very serious problem.
I know some people who say they don’t know what they would do if they were retired. My experience tells me that you will, or can be, very busy. Busy, but busy doing exactly what you want to.