Anyone else trying to lose weight while experiencing migraines? What helps?

Like I get lightheaded when I'm on a diet, I have migraines when it's hot outside, and I also get migraines when I focus too much on school work. I've seen a neurologist before but everything came back "normal" and they were ultimately useless so I stopped seeing them and just dealt with it. It's been 3 years now but these days it's just extra bad and takes a toll on my energy so much. I'm always tired no matter how much sleep I get too. How do you guys cope with this?