Can you tell me how i could lose weight and live healthy if i feel sick and weak every time i try to eat healthy and exercise?

Dieting weakness: I would recommend a healthy high protein low carb low glycemic diet. Make sure you eat adequate protein before trying to exercise. Your weakness experienced when you exercise may be from improper intake of food before exercise. Start slow with exercise even just walking 20 minutes a day then build from there.

Remember: No one is allergic to all healthy food choices so this means that you just haven't found the right selection of foods that work well with your system. There are those that can be allergic to exercise(this is exceptionally rare though.) It sounds like, just with an optimal diet, you just need to find the right type of exercise routine for you. Consider talking to a nutritionist and trainer.