Good, better, best

You are correct - you probably wouldn't say "you are my better friend" in English, so I'm not sure why you would even want to try to translate it this way. "Meilleur(e) que" means better and "le/la meilleur(e)" means best. It's the same concept as "plus que" for "more than" and "le/la plus" for "the most" e.g. Pierre court plus vite que Jean, mais c'est Usain qui court le plus vite. Some examples of this concept (comparison vs superlative) with meilleur(e): Fred is a better friend than Joe - Fred est un meilleur ami que Joe; Sarah is a better cook than Isabelle - Sally est une meilleure cuisinière qu'Isabelle; He is my best friend - Il est mon meilleur ami; Jane is his best friend - Jane est sa meilleure amie; I am a better cook than my brother but our father is the best cook in the family - Je suis un meilleur cuisinier que mon frère mais notre père est le meilleur cuisinier de la famille. Hope that helps.