I can only observe others as I'm no where near that age. The ones that seem to me the happiest are the ones with something to do other than watch TV all day. They shuttle grandkids to school and attend all their extra-curricular activities. Some even get part-time low/no stress jobs just to have something to do productive--even if they don't need the money. My point being, find something to do, to make yourself useful. If you don't have enough to do maintaining your property, then volunteer to help somebody out that can't pay you back. Even if its just visiting old folks or running errands for them. Just don't retire to a rocking chair all day if you are able to do something.
Hey you could always apply for an internship at OCC.