If it's mid september, you can totally do it. Regain your focus, NO cheating and continue your workouts. I really know what you're talking about and I'm on the same boat right now. I have a cruise in september and 20 lbs left. I've easily lost 10 lbs a month until last month, where it suddenly became difficult 'not' to cheat. I've become more diligent in the past couple weeks and now hoping to move the scale again. good luck to you (and me)! like NEMom says, you'll still feel great on your vegas vacation if you continue your plan, even if the scale isn't exactly 20 less