I remembered when I had to read S&S for school, being surprised at that attitude of "the novel's supposedly happy ending for Marianne is false", presented by many critics. The idea seemed to be that her marriage to our dear Col. B. turned her into a "tame shadow of her former self" (I quote from memory) and was somehow emblematic of the oppression of spirited young women by marrying them off to older men, etc. etc., with hints that it would almost be a "marriage blanche" (but let's not go there, we're PG-13!).