Hi sweetie.... if you can't speack to your parents.... you need to find someone else you trust Counceller, friend, relative... anyone who can show you support! You are not alone in your dilemma, and may not even be bipolar?
I would try whichever parent you feel more comfortable with... and if this does not go anywhere... then seek outside support. You might just be traumaticed with your parents fighting... I am assuming you are in your teens?
I do have a daughter and have always encouraged open discussions.. whatever these might be, and told her that "I love you no matter what"
Hugs again little sweet pea!!!!!