I think that redefining your measure of success is key.
Losing lbs on the scale is not the only measure of success.
Do you make healthy choices more often than not? (Or even more often than you use to?) Yay improvement.
Do you feel stronger than you did when you started? (start weight training its AMAZING for your self esteem after you get going)
Noticing the things that you are capable of when you get further into your journey really helps. (Yay me I can help a friend move her couch, or carry a 70lb luggage now!)
And yes I may never reach a medically approved goalweight, but I AM healthier than I was in April. I can do more, and if all I can manage this month is to maintain my weight. Well that is still great because its not gains... I've maintained since August but thats better than ballooning up and past 370 again so... just hold onto the tiny wins...