It definitely is a different life style. I do all the above except medication. I am able to control it IF I pay attention to what you mentioned and also my stressors. There are some foods that exasperate my symptoms, and some that help moderate them. Listen to your body. If I drink fresh juices, usually I juice apple, carrot and cucumber in the mornings, eat fresh, raw veggies - like a good salad for lunch (sometimes with chicken or tuna on it) and maybe steamed veggies and whatever for dinner, I do pretty well. But I also cut out junk food and sugar - those are killers. Also gluten and dairy can be harmful to many.
Next, I limit my physical exercise. This has been really hard, but if you have post exercise malaise you have to. If you exert yourself you will end up in bed anywhere from 24 hours to 2 weeks after and it could take weeks to pull out of it.
Supplements help me too. Vit D, multi vit., probiotics and omega 3
Finally, reduce your stress. If there are things that make you stressed, like school work, cut it back. I know that our society says you need to stay on this invisible time line - graduate at this point, go to collage, graduate college by this time, etc., but this is not so.
I have lots of kids and each one has done their education different. There are many options these days. My favorite one is the duel credits available today. I don't know what state (or even if you live in the States) you live in, but where we are if you don't have your diploma or GED you can take early college from the University at a fraction of the cost than if you did have them. For instance, you can take a duel credit course for $65 per credit verses paying $265 if you graduated from high school. Many of these courses are available on-line allowing you to save on travel, or in the high school. Take one class a semester. So what if it takes you 2 more years to graduate from high school, you will be earning your college credits at the same time so you will still be on track - if you are concerned about that. Relax and give yourself permission to change the rules and do things differently.
As for the depression and anxiety, I believe that the change we have to make in lifestyle can increase it, but I also believe that it is a symptom all on its own and no matter how well we are doing they will be there. The anxiety is the worst for me, I am constantly fighting it. I wake up several times a night with little panic attacks, drives me nuts. Recognize that they are symptoms and not who you really are.
I am sorry you are having to deal with this at such a young age. I have read statistics showing that if you do get this at a young age, you have a chance of pulling out of if in 5 years or so if you can keep your symptoms low. Hope this happens to you.......