It took me about 10 months to lose 12lbs. I started off at 212lbs and just couldn't picture myself getting back into the 100's. For all that it was just a number on a scale, dipping below 200lbs just didn't seem real.
Now I'm 40lbs less but in the same situation. My mental roadblock is getting into the 160's. I've gotten down to 170lbs twice since last summer. This time I'm going to succeed and push past that number into the 160's!