The place people return to on uneventful days has become part of their actual happiness.

Happiness is more accurately measured by ordinary days than by special ones. The café, the bench, the shop, the route people take when nothing is happening are the places actually holding up their week, even though nobody would list them if asked what makes life good. Special occasions are memorable. Repeated places are structural.

Write down where you have gone in the last month with no particular reason. Then look after those places: spend money there, say hello, tell somebody about them. What is unremarkable is easiest to lose and hardest to replace.