Why do we feel nostalgic?

Nostalgia, then, seems to be one way that people cope with various negative mental states, or “psychological threats.” “If you’re feeling lonely, if you’re feeling like a failure, if you feel like you don’t know if your life has any purpose [or] if what you’re doing has any value, you can reach into this reservoir of nostalgic memories and comfort yourself,” says Routledge. “We see nostalgia as a psychological resource that people can dip into to conjure up the evidence that they need to assure themselves that they’re valued.”