The Underwater Part of the Iceberg

The "hard-eyed" bull-fighters and bull-critics at the bar stared Jake as he left Brett alone with Romero.  He says, "It was not pleasant." (pg. 191).

How much is it possible to imply in one short sentence?  I think this is the epitome of the tip-of-the-iceberg idea that is used to describe Hemingway's method of portrayal of human life.  Jake is referring to the unpleasantness of the entire situation.  In terms of his own feelings, he just answered "Yes" to Brett's question, "Do you still love me, Jake?" (pg. 187), and is now leaving her alone with another man.  Additionally, he knows that she really feels close to him.  She tells him he is the "only person I've got" (pg. 185), even though her fiance is present in the town as well.  Yet, we know that she would not want to technically stay with Jake for her life, because he is incapable of giving her sexual pleasure.  Thus, she has also told him she feels like "such a bitch" (pg. 188), three times (probably meaning for having gone off with Cohn, for wanting to pursue Romero, and for being really attached to Jake, even though she is not physically attached to him, and for not really being too in love with Mike).  Thus, Jake is also dealing with Brett's guilt while he leaves them, and the knowledge that he could be in Romero's place if it were not for his war wound.

The fact that he had to walk away to the disapproving stare of the bull-fighters and bull-critics did not make his situation any easier.  He had had a conversation earlier that day with Montoya, and had recommended that Romero not go to the Grand Hotel, because such drinking and partying outings might destroy Romero's bull-fighting career.  It probably occurred to Jake that alone-time between Romero and Brett could be just as bad for Romero as going to the Grand Hotel.

Jake was probably also looking toward the future, when not only Montoya, but also Mike and Cohn, would find out about Brett's escapade.  If Mike's knowledge of Brett's affair with Cohn was not enough to put him over the edge, then his knowledge of her new affair while Mike was present, as an option, in town, would really make him mad.  Similarly, since Cohn had apparently been staying around simply because he thought Brett liked him instead, Jake must have known that this new affair would make everyone mad.

Therefore, when Jake left Romero alone with Brett, he was probably doing it because he loved Brett.  It was what she wanted, even though she knew it was not what she should do, would be expected to do in society, but it was what she wanted to do.  And she knew that Jake would be the only one to understand, and that no one else could ever fully understand.  Thus she left him the unpleasantness of leaving the two of them alone together.