I'm motivated even more now by the fact that I have a little less than halfway to go before reaching my goal. The hardest part for me was being motivated enough to start while understanding that it was going to be a long, slow process. I've been on this journey now for 3 years (I maintained a 70-pound loss through 2012 and I finally am in a position where I can start losing again).
I agree though, the more you work, the better you feel. The better you feel, the more you want to feel better.