I have not changed my goal weight as I still look a bit pudgy ~5 lbs from goal, but if you are wearing a size 6 at 5'8" tall, you probably look and feel long and lean. Who cares what you weigh in the end? It's more about how you look and feel.

BMI is a not a good gauge for everyone, but again, if you look good and feel strong and your BMI is in the normal range (which yours is), then your body's stall is probably an indication that it is comfortable at this weight. I say you adjust your goal and call it done.