In Melody Beattie's book codependent no more, on pages 196 & 197 there is a story about the journey of healing in codependency and it compares counseling with alanon. IMHO, one cannot heal without alanon. I'm sure there are the exceptions, but I've never met anyone. As others have said, it's a process, like learning a new language. You don't "get it" in one meeting.
Takes several, & different meetings to find the right one for you.