Does one need parents in their life?

I've got a father who is continually judgmental and also, possibly bi-polar without taking any medication or seeing any psychiatrist. My mother is better, but also sensitive and too overly-cautious (sometimes, even too negative).

They have good hearts, but as parents, it seems like they are not good. They help me with financial issues when they arise, but it feels like one of those abusive relationships, ya know? Where there are too many mental issues clouding what the emotions are.

I guess I am trying to ask is if do I have to be in touch with them for the rest of their lives? I am the only child and I know what I am asking, I'm just frustrated and feeling like every time I am around them, I am not my best self.