Firstly, I just want to say that I'm so sorry your mum is being like this with you. Really. If you do need to lose weight then you need support and guidance and care - you do NOT need crash diets and your mum acting as ridiculously as she is now. At the end of the day, it doesn't matter who's at fault (if, indeed, anyone is at fault) for you being overweight. It's just the way it is, and I think the important thing is to work on getting to a healthy weight, y'know? In order to lose weight you NEED to eat. Starving and not eating won't help you at the end of the day - it'll just lead you down a horribly dark path and you may end up with eating issues for a long, long time. Not eating won't make it all better, it won't help you any, and at the end of the day, it'll just make you even more unhealthy. What you really need is a healthy, balanced diet and and exercise. Regular healthy meals, and regular exercise. These two things combined CAN help help you lose weight - and can help you maintain your new weight. I get the feeling that your mum is acting out and is being incredibly irrational about it all. Maybe she just doesn't understand how someone goes about losing weight and maintaining that weight.
Would it be possible for you to visit your doctor and try to work out a healthy eating plan? Honestly, it's so important that you DO eat and your mum is being really ridiculous in not cooking you meals. Could you possibly try and have a chat with your mum about this, and explain that starving just isn't going to work and could you both visit your doctor and work out a new diet? Combined with that, regular exercise will also do you good. Going to the gym once or twice a week, taking up a sport, or just exercising about your house - all of these things can do the world of good. You could also go on the internet and find some websites that tell you about the affects of starvation on the body, and show these to your mum, just to let her know how detrimental this can all be to your health.
Best of luck to you! Losing weight in the correct way can be a long process, but it's absolutely worth it if it gets you healthy. Have a talk with your mum, yeah? Really, good luck.
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so if you're crazy, i don't care you amaze me