Interesting question. I think about this a lot too....

Situational depression could lead to an actual depressive episode for me. The thoughts become darker, more negative, and overpowering. Sometimes it turns into a mixed manic state where it triggers paranoia and racing thoughts. Also, going through bad situations often increase rapid cycling in me.

I wish I could let go of things easily, but I can't. Those of us with BP or a mood disorder are especially vulnerable when negative life events or changes occur. I think therapy plays an important role though in addressing situational depression, especially Cognitive Behavioral Therapy to help work on coping with and challenging self-defeating thoughts, or at least having the support while dealing with certain situations (along with the help of meds though).