The constipation is certainly behind your symptoms, including brain fog. Important nutrients your body needs for proper brain activities are absorbed through the large intestine, which doesn't happen when it is blocked up and backs up waste towards the chest and head (acne).
To be so constipated bile flow must be very scarce. You didn't mention how much you have released during those liver cleanses you have done, but obviously there is a lot more in the liver that blocks the bile flow. As mentioned in my book, to end a chronic condition, the liver must be free of all stones. Even 10 samll stones can cluster together in one of the tow main bile ducts and prevent any bile from coming out of that duct, affecting the digesiton of food and elimination of waste from the colon.
Also, please don't underestimate the power of emotions. If you are holding on to an old resentment, anger, fear etc., your body will become tight and do the same with food/waste. The emotions related to Bulimia are deap-seated and can resurface years later to bring them to a conclusion. You may wish to look into that.
Make sure to eat a Vata pacifying diet to avoid dryness and hardening of stools in the colon (see my book Timeless Secrets of Health and Rejuvenation).