Never ending "lifestyle change"

vb2305

I have been following a diet plan successfully for almost four years now and have lost 140 pounds. This year has been very hard for me...it is the first year I have not lost weight. Instead of losing weight like I did the first three years, this year I fought just to maintain my weight. And this weight is not even my goal weight which is the most depressing part! I'm starting to feel overwhelmed by my "lifestyle change". I currently do some sort of physical activity everyday of the week...three days a week I play competitive volleyball, five days a week I am training for a half marathon, on weekends I go for 50+ mile bike rides, and I see a trainer once a week for weights. If I do all this, and follow my diet plan (~1700 calories/day), I can lose a little bit of weight. But as soon as I miss a workout, or indulge in a sweet snack after dinner, or maybe go out to eat, I gain weight. It is never ending! I am only 25 and I constantly think that I cannot do this for the rest of my life! But I don't want to go back to where I was before.

I still have trouble with food, and find myself with major cravings a few times a week. Most of them I get rid of, but I inevitably give into one that leads me to eating my days worth of calories on my way home from work. I also find that I go through phases...a couple weeks ago I was pumped up about eating better and lost five pounds in one week just by strictly sticking to my diet. This last week I haven't even weighed myself since Thursday or so because I want a few days to recover from my awful weekend before I look at the number on the scale.

Anyone else on a roller coaster like this? How do you stay motivated?