My brother was diagnosed with Bipolar Disorder (NOS) and I have been diagnosed as having Bipolar2. We are dealing with a family crisis that involves our mother and her recent cancer diagnosis. My brother is experiencing a manic mood, thinks he is an expert on cancer and has taken control of decision-making for our mother's care. This has caused a lot of confusion with the family members. I am experiencing a hypomanic mood in which I feel that my personal experience as a cancer patient (recovered) provides insights and knowledge that he lacks. I'm trying to figure out how I can deal with him when we have a disagreement so that it doesn't stress out our mother and our two sisters.

Has anyone else been in this type of situation?