Why does extending Metta to all beings hit mental exceptions and deepen my sense of isolation?

The guide then requests me to wish goodwill to all beings but my overthinking picks up quickly to make exceptions: okay, other than the driver who cut me off, or except me. It is interrupted by this continuous mental resistance and sense of isolation. Is it a defense mechanism of the psyche or is it part of the normal learning process to get rid of this life theme of being different from the rest of the world? My name is Riya, and I was born on 14th July 1994. Time: 3:45 PM. Location: Delhi.