For me, it's goals goals goals!
For each 10-20lbs lost is a reward. Since I've lost 30lbs, that means that I get to go horseback riding (cause before, I wouldn't go because I felt too overweight)
At 40lbs (If I make it before the amusement parks close for the winter) A trip to an amusement park and a day of roller coaster heaven!
That really helps me. Also, setting a good example for my step-kids, showing them that hard work and dedication really pays off in the end.
I hope that helps!