She wasn’t expecting Scott’s call. Ever since he came back from London, the only time she saw him was when he went to NYU to have his meeting with the board.
Florence didn’t know what to think of it, but she was well informed on how things worked nowadays. Lack of communication was communication enough. If someone didn’t care to call or even message you, they probably didn’t want anything to do with you anymore.
That’s why she began to think that Scott’s absence implied exactly that; he was tired of their little affair but didn’t have the guts to end things with her in a nice way.
She even allowed herself to be mad at him for a while, before trying to move on, but his call came before she had the chance to do that.