I still struggle questioning myself too. When I first started talking to my therapist I started journaling as well trying desperately to figure out which parts of my past were due to my BP. I've seen articles asking the same question. Which part is me and which part is BP? So, I know it's something that a lot of people with BP struggle with. I filled journals with questions and research trying to figure out how my cycles went. It's helped me out a lot in figuring myself out. While a lot of people don't care to go deep soul searching, I found it pretty helpful.