Not sure what happened to my first answer but I will type it again.
I was just telling someone the other day that it is a true mental test to both lose and maintain weight-loss. It is a constant battle to make the right choices about what to eat and motivating yourself to exercise. It is best conquered by making healthy eating and an active lifestyle part of your routine; that way you can stick with it. Find those things that motivate and inspire you to keep you going! I'm now taking a liking to triathlons so that definitely keeps me in the gym!