The diet is too much to handle becaue you're making yourself uncomfortable. If you make yourself uncomfortable with dramatic lifestyle changes, you wont stick with it. I think what will work best for you is one or two small changes at a time. That is how a lot of people do it. My mom used to be big as the side of the house and she started with small changes. First she gave up candy bars and after a week or so she gave up cheese burgers then after another week or so she started walking a little bit.... and just gradually keep adding those small changes. Shes fit now.
I think you could benefit a lot with some nutrition or fitness coaching. Most people need that because they want to change and have all the drive to do it and stick with it, but just don't know what to do or how to start.
Small changes make all the difference. I don't know what you do all day but one small change could be to just start taking stairs instead of an elevator... or if you have whole milk with your cearal, switch to skim or 2% just things like that. Or, if you eat breakfast as school, instead of having the biscuits and gravy, have fruit and oatmeal or whatever else is available that's a better choice. Or stop having ketchup with your French fries (its all sugar). It really does work.
I've spent lots of money on diet clinics and stuff that use drugs or put you on a really strict diet and the results never lasted because it was just too dramatic and I went back to the same bad habits. The only things that ever let to lasting resuts was the small changes that I stuck with... like parking far away from buildings and walking through the parking lot rather than parking as close to the door as I could... I've even joined extreme fitness classes like crossifr and never stayed with them because it was just too much all at once.
One thing you can do that you wont really notice is don't eat everything on your plate... leave like 20% of it. At the end of the month, all that food really adds up.