In hte earlier part fo the book IMO Mrs J is written very much as a caricature and not nearly as likable as she becomes at about midway through. She is gossippy, and loves to speculate and to be intrusive.. and has no concept that she might hurt or offend others through her constant outspoken chattering. She is vulgar and not always that clever. When Elinor is considering going to town with her, she does not really wnat to go becauase among other reasons, Mrs J is IHO vulgar and will not be an enjoyable companion or ladylike enough to give them "consequence" as their chaperone..