I suggest researching MK-Ultra to find out how the fragmentation of this dysfunction has been used by western governments in secret to attempt to create completely mind controlled slaves. In short, they took over research from the german nazis at the end of world war 2 and carried on using torture and trauma to split the minds of people and then program sub personalities into them which were unaware of the other personalities. The sub personalities can then be triggered at a later date to perform missions and then go back into hibernation. This means that, for one, the person will not give up any secrets if captured and tortured.

This is a large part of why these mental illnesses have not been healed more effectively. There is vested interest in us not understanding them.