Hi Marina (what a beautiful name!)
I am a T2, and so my issues are not the same as yours, but I want to point out that you look like an attractive young girl, with so much to live for, and the idea that there is a great guy out there looking for you, is important to remember, because when you find each other, you want to be in control and condition so you can enjoy all that life with him will offer you. Don't deprive him of the special person that Marina is. He deserves the best you have to give, even if you don't know him yet.
Motivation is a problem for a lot of people, and its not just over diabetes. Again, my condition is not as complex as yours, and I don't need motivation to cope with the diabetes. Its all the other things in life that I am failing miserably at, like finding work, finding someone to love who loves me, and deciding what to do with what remains of my life. I would venture a guess that you are just a normal 16 year old, and that in itself means you really don't want to have to think, you just want to have fun. You are entitled, btw, but remember its part of the maturation process to find it difficult to overcome obstacles.
Pigging out when you know is wrong, is just the self destructive side of yourself, rebelling against what has happened to you. That will not go away until you replace the desire, with something constructive. If you didn't have diabetes, you would be unmotivated in other areas. Its not a shot at you, its normal and natural.
Baby steps, and small changes are your best bet. Doing anything that drastically alters your lifestyle will likely cause you to fail. You say that your numbers are okay when you manage them, so your problem is the "pig out" urge, which is simply your way of rebelling. Attack that urge, and break it into manageable events, and then reduce it from there. I don't know what you pig out on but say its brownies, for the sake of making the point. If you eat four brownies, just eat three instead. Instantly, you reduced your intake by 25% which is an improvement. Over time, you will be able to reduce by another brownie, and now you have cut your bad intake in half. That's a pretty big step, and will make a difference both in your control, and in your state of mind. It might take a while, but that will be a big accomplishment, and your numbers will reflect that change for the better. Winning is a great motivator, so set yourself up, so you can win.
There is no way you are going to just quit over indulging instantly. That is asking an awful lot of anyone. It takes time to effect change. Baby steps.
I would very much like to teach you all that I have learned in my lifetime. I have made every possible mis-step, and screwed up so many things, its remarkable I have gotten this far with my brains anywhere near intact. The world is out there waiting for Marina to take it by the horns and subdue it, yet my recollection of being your age is that such a thing doesn't matter to you yet. Best advice I can give you is, it does matter, and you don't have to turn your life around on a dime, but start turning it a little bit. When they started flying to the moon, they had a long journey, and so course corrections we small, but over the length of the trip, a small change in direction made a huge difference their course over time. Same with you life, and your habits. Small changes may seem irrelevant right now, but given the length of your journey, those small course changes will result in big changes over time. You don't need to correct your course 100%, right this very moment.
When you start to save money, its hard because there is only a few dollars in the jar, but the more dollars you put in there, the more you begin to see the benefit of the savings. Make tiny changes right now, and note them, and soon you will see benefit to changes, and be wanting to make bigger changes over time.
I have foot problems that are not related to diabetes, or so I am told, and I cannot walk very much without a lot of pain and suffering. Hiking the backcountry of the Rockies is what has kept me going the last few decades. Now I cannot do that, and although I cannot blame the diabetes, I am sick to think that it is the result of something that I could have avoided, if I had taken the time to better care for myself.
Please don't let the last thirty or forty years of your life be pain and suffering, filled with "if only" and "What if" all the while second guessing yourself over choices you made when you were young.
If you want to talk, lets chat private. If you want to vent, or rant and rave, I am one who will listen and will not judge you. I am someone who would love a second chance at being a teenager, because now I see how important it is to have fun, be a teen, but I also now know how important it is to keep an eye on the future.
Trust me when I say that when I was your age, I looked at calendars, and saw the year 2010, and never, ever though I would live to be that old (54) so I screwed up, and didn't make the right choices. None of those choices would have interfered with the enjoyment of my youth, but they would have gone a long way towards making my present condition more enjoyable, and fruitful.
Life is a long journey, and you can't pack for it like you are just taking a three day weekend camping trip. It takes more than that.
Motivation is something every person deals with on a daily basis. Remember its probably not just the diabetes causing it. Its simply where you are in your life, so work on it, from that perspective, rather than focusing on this damnable disease.
Nuff said, hope I didn't offend, but be sure and post, and vent and rant, and as I said, if you want to keep it private and anonymous, I am most happy to listen and try to help you.
The human spirit is a remarkable thing, and can drive us through some of the most gosh awful things that we are sure we could never survive, yet we somehow manage. You can do this. Just let others help when they can. You are not alone.