The weaponizing of the extreme mental states as an adaptation to gain a feeling of stability and an experience of control is something therapists don't look into because their model of "human nature" is that we are all the same, fundamentally, with a bit of corruption here or there (a bit of pathology). I think this is a problem that stems from the fact that a religious model is being used tacitly. If an organic, natural, evolutionary, biological model were to be used, it might be easier for the therapists and the like to observe very different functioning, just as you would observe differences between various species of plant. But the "soul" model does not allow them (or us) to think in those terms of natural, organic adaptation, to facilitate survival.