My uncle was trying to insult me

Because my cousin has just passed her driving test near mine and she went with her dad (my uncle) to buy their first car. It was a Mercedes A Class 2004 and I asked why they didn't buy a fiesta then he was like they don't buy crap like that then he said there's 2 Mercs n the drive and one Ford (my uncle has a c class) but he was trying to make me feel bad about that I drive a Ford saying its crap and stuff

Just ignore him.
He may be trying to feed his own ego by subjecting you to humiliation tactics or want to bait a reaction from you and start a fight.
Life is too short to waste your precious time and emotion on those that don't deserve any.
Good luck!