You said this yourself, so don't look at me badly for saying it. I don't think modeling is a healthy job. Models are like strippers that you pay to wear clothes instead of take them off. You're both selling your body out to look pretty to someone else's standards, because you like the money. The main difference is your job's labeled by society as legitimately respectable work because we have some weird phobia of our own bodies that makes nudity disgraceful. Put beads over your nipples and suddenly you're classy for acting French =p
Obviously I'm not commenting on the work you've done as I've never seen it, but what I am saying is that the job itself requires an unhealthy mentality and puts WAY too much of your life's focus on the meaningless aesthetics and that's almost the limit of your qualifications. It's easy to feel uncomfortable about yourself, or unstable about your eating habits when there's so much riding on it. It's like pushing a button because someone told you not to.
And you put yourself through it for the money. That glorious money that's so great that you're so happy binging on tubs of ice cream so you feel disgusting enough to force yourself to exercise and eat right again.
Money's fun, but it's worthless. You can buy stuff with it. You wont be happy. You can buy nice clothes, you still wont be happy with your lifestyle. So what's the point on having all that money if you're uncomfortable and stressing out like this?
I just think it's sort of warped that here you are, someone who seems to be in good overall health taking care of themselves properly, and yet you're still fighting strong cravings and eating disorders with what sound like issues of self image, and feeling disgusted at gaining a few pounds here and there. Something about that doesn't seem right when you look at it like that, does it?
This doesn't entirely sound like someone who's living well for themselves. Get some work that makes you worry about something other than how many centimeters you've gained to get your mind off the importance of your weight (muscle weighs more than fat anyways, so even your weight isn't a great measurement for your body's health. Plenty of the world's greatest athletes have rated as morbidly obese on their BF ratios while being considered some of the most fit and attractive athletes in the sport). If you love modeling, great, keep doing it, just don't live for someone else's expectations. Especially if they're just paying you to prance around in pretty clothes so they can sell those clothes.
Health and happiness are priceless. If you can't maintain the two in synchronization, your lifestyle isn't working for you. You're never going to wake up and decide you don't like chocolate anymore because you're too healthy for it. It's just gotta become who you are, and how you act is largely, if not almost entirely, based on your circumstances in life. Know what's good for you, listen to you body (it WILL tell you what you should be doing or eating if you learn to pay attention to it), and keep your sense about it. You don't have to be as thin as you can be. Any organism with its goals that out of whack would never thrive successfully. Body fat plays an important role in your body. Don't hate it just because you can acquire too much with abuse.