I know you feel like nobody is listening to you and that what people are telling you doesn't make sense based on past experiences but I hope my story can help a little bit:
I have been overweight all of my adult life and only lost through serious calorie restriction and tracking everything (I'd lost 3 stone at WW). I gradually put this back on as after my DF died I couldn't get into the right mindset to track everything. I'd also suffered from debilitating migraines (I once lost the ability to speak for 6 weeks) and couldn't eat cheese, drink red wine or have msg without triggering a migraine (other things periodically set them off too like processed meat).
Then last year I broke my foot really badly and had to be immobile for 3 months. After 2 weeks I could feel the weight piling on, I was depressed, fat, sweaty and uncomfortable. As I couldn't move and was reliant on others I couldn't control my diet and couldn't move. Obviously I had lots of time for mnetting and read the boot camp threads. Honestly it made no sense to me, and I couldn't imagine it working. However, I thought it was worth a punt as it was possible to do in my situation. I honestly just hoped I could avoid putting weight on. I was absolutely amazed that within a few days I could feel that I was getting slimmer. Amazingly I lost 2 1/2 stone in a period where the most I moved was to the bathroom and back. I ate lots of fat and probably more than usual in the beginning due to boredom.
Alongside the weight loss the incredible thing is I have had NO migraines for months and now eat all the things that triggered me before. The one time I had one was when I decided to see what it would be like to have chocolate a few months after beginning low carb eating (it's vile- your tastebuds totally change so it's all just sweet and oily) and demolished a tomblerone 
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I would be lying if I said it was cheap, BUT- only got the first few weeks, you really start having so much smaller portion sizes. Today for example I was so full from a late lunch I had out (moules) I've just had some Greek yoghurt and a few raspberries with a splash of cream and I'm absolutely stuffed! I never would have believed that before and could easily have eaten 4x that amount. There are cheaper things too like chicken wings and legs, lamb ribs, curries with coconut milk and cauliflower rice, corgetti and meatballs with cheap mince.
I've done quite a bit of reading around it since and understand the science a bit more but even I can't quite get my head around it at times. It involves such an adjustment to what we've always been told (and sometimes even seen in our own bodies-eg migraine triggers) that it's hard to believe and I still feel weird doing things like asking for cream to go in coffee.
What I can say is that I've never been slimmer or healthier. If my broken foot hadn't pushed me into that corner I'm not sure I would have tried it (honestly I thought it was unhealthy, dangerous and not likely to work long term) but I'm so grateful. I now have just 10lbs to be a healthy BMI (I needed to lose 4 1/2 stone at first) and don't live in fear of migraines, my dodgy joints are better and my acne has cleared up. I'm not as strict as bootcamp and very occasionally have something carby (a special occasion where there's no other options or to share something homemade at work) but it really is occasionally as I don't want to eat that stuff now.
OP you obviously have more challenges than most but I really think it's worth a shot, if you stick to it you will lose weight and your health might just improve. I'd say give it at least a fortnight as by then you should have got over the carb hold and started wanting smaller portions ergo it becomes cheaper.
Good luck!