Neutrinos.
Neutrinos are bizarre, they never bond with one another, they're always alone with nobody by their side humans r quite the same, surrounded by billions of people crossing paths, sharing moments but never really connecting, we brush past life the same the neutrinos past thru matter; silently, invisibly leaving no trace behind. A person can smile with their friends in a classroom then go home and sit in their bedroom in grief and anger wondering why it all happened? And how nobody truly ever understands how they feel. It is possible to talk all day and still feel unheard , to be surrounded by voices yet feel Invisible. However unlike neutrinos humans are capable of something extraordinary, a genuine conversation, a moment of being heard, a hand on ur shoulder and a hug from someone telling you it's all gonna be okay because truly the difference between feeling like a neutrino in a universe and feeling like human is just one real bond.