I am a Type O blood type and I get HUGE cravings for animal protein when I avoid it. Do you have any pointers?

I have type O and never have cravings... it sounds like you're not craving meat, but some nutrient you've come to associate with meat. I would suggest having your iron and other nutrient levels checked. Your body might be associating a specific nutrient with meat. You can also check out my posts on Food Cravings and Food Addictions and Dealing with Food Cravings.