Are Peter and Brian still best friends?

I haven’t really watched the newer episodes from this season but back in the day Brian called peter his best friend but I guess after season two or three Brian has been Stewie’s best friend. And honestly I feel skeptical that they were ever really friends to begin with. Brian is a pretentious atheist liberal failed book writer and college dropout while Peter is just a fat drunken idiot. They really have nothing in common to begin with.