When I'm stable I react appropriately to life events. When I don't I know things are off. But of course this assumes you have stable periods. When I had both PTSD and BP it was very hard and the times of stability were few and far. Finding the right meds is also kind of a crap shoot, throw in monthly hormonal changes which can be hard for normals to handle, it can get very difficult to know whats personality and which is the illness. They best bet is to work with a good therapist and learn to identify your personal cyclic patterns.