This is also the wisdom of the fantastic 1930s(?) book LIVE ALONE AND LOVE IT. Everyone needs 2 hobbies at least - 1 that you go out for and 1 that you do at home. Applies whether or not you live alone!
One of the great joys of my adult life has been realizing that I can just pick up a new skill every so often, take a fun little class in it weekly for a year or two, and simply enjoy meeting people and getting medium proficient and not attempting to become professional in it at all!