Classic literature is sorely lacking when it comes to certain themes

Where are all the great fiction books that deal with topics like the following: fear of aging, fear of losing one's parents, fear of serious illness, losing one's job, feeling like one is very poorly suited for their current career but unable to pivot, feeling like one is destined to never find true love? There are any number of classics that deal with themes such as social class, justice, and romance but they rarely seem to delve into the more existential struggles of daily life. Recommendations welcome!