I echo what the others have said, especially in terms of cleansing- it's amazing how many craving go when you've done enough bowel and liver cleansing- that has been my experience. Also, you may need to eat more fruit. We are designed to eat fruit, and it is so easy to digest. Many people avoid it because of the Sugar content or worrying needlessly about carbs- but it's exactly the kind of Sugar we need for our brains to function and to help fuel our cells. It's also incredibly alkalizing and detoxyfing.
I think Sugar and chocolate cravings happen because we don't eat enough nurtient dense foods that we are designed to eat! Try upping your intake of fruit, and also leafy greens- since they are so full of minerals they may help quell those chocolate cravings too. You can combine both and make awesome green smoothies!