Omigosh... I do understand! Chocolate is so addictive. I can't keep it in the house. Occasionally I give in, but then I banish it for a while. Itching half the night sounds awful. My usual symptom for telling me I ate the wrong thing is migraine headaches, with or without an aura.
The thing that has helped me the most was overhauling my diet completely. I know this will be annoying for some to read, but I became vegan 2.5 years ago. Eating dairy and other animal products gave me inflammation that led to a host of problems. My migraines are almost gone, along with my knee pain, general osteoarthritis pain, psoriasis, IBS, constipation, high cholesterol, elevated sugar, elevated blood pressure, cysts in breasts, acne, gingivitis, excess weight, moodiness, etc..
If I start to have a food craving now, I eat some trail mix, carrots and hummus, or nut butter and AllFruit on toast and I'm good.
The foods we LOVE can have horrible consequences. Eventually we learn that those few minutes of extreme pleasure are not worth it.