Hey there --
I think you have a lot of good observations and information about yourself, and I'm glad you posted here. It seems to me that you just need to go to the next level and put all this good info together and work out a lifestyle that works for you.
I'm glad that you seem to be OK with the fact that the scale isn't that big a deal as long as you are healthy. Some people just aren't meant to be Kate Moss, ya know? So good for you for recognizing that. From this side of the fence, it seems that what would benefit you the most is simply balance. Your body is young enough that you can lose weight without really trying, but as you've recognized, binging and eating junk isn't good. And, as you age, the ability of your body to bounce back from extremes will diminish. Sad, but true.
So, I would offer these basic tips:
Find something besides food that will help you deal with emotions, difficult people, and the general ups and downs of life. It's not enough to say you're going to be careful about food, stick to a food plan, etc. You have to find things to REPLACE what the food did for you, and to even learn how to manage emotions before they become a problem. For some people, this "thing" is religion. For others, they may need to pick up some stress management techniques, or to meditate, or to journal, or any combination of the above. You might try yoga -- if you look for a beginner class it's not that difficult, and it's amazingly calming and restorative in addition to being good exercise. I can find a million excuses not to do a cardio workout, but I wouldn't miss my weekly yoga class for the world.
Next, find a good balanced food plan. It sounds like you don't have to be that strict about counting calories and whatnot. Just concentrate on eating a balanced diet and eliminating the junk. Feed yourself quality fuel throughout the day. You might want to follow a written plan for a while to get a good foundation, just don't think of it as a "diet."
Finally, activity is good. Again, you want to make it part of your overall life. Weight training will do more to reshape your body than anything, and cardio will help keep those calories burnin'.