The reason peanuts are a no-go food for primal is that they are not nuts. They are actually legumes which are on the list of things you shouldn't eat because they have a lot of phytates. Also peanuts are frequently contaminated by mycotoxins which are also not good for you.
In addition they are quite calorie dense without much in the way of nutrients (which is the case with the true nuts also.)
My recommendation based on your first post would be to go fully primal for at least a month. If you haven't read the book, do. If you haven't read the primal 101 posts, do. And I know how much of a pain in the ass counting calories and such is but I would do that too for at least a week. My biggest problem when I first switched to primal is that I felt super tired. I finally entered a weeks worth of food into one of the online food tracker things and found out I was only eating about 800-1000 calories a day! No wonder I was tired! I was eating a good VOLUME of food but it was mostly greens that take up space but don't offer many calories. Once I upped my calories I felt all better!
Also there is a particular poster on these forums who was significantly underweight and used primal as a way to heal and put weight on. I can't think of her name right now so maybe another poster can help me out here?

Anyway she wrote a really good journal along the way so you might want to read that too since you are concerned about losing any weight.
Make sure you are eating plenty of calories, go fully primal for at least a month (you have some serious chronic symptoms so commit to no cheats for the whole month!), and give it some time. It sounds like you have been dealing with some chronic symptoms for a long time. Everyones body heals at a different speed. Treat your food like the medicine it is and give your body time to heal. And we'll help and encourage you but you have to be the one to do it! No one else can fix you the way you can.