What to do about my mom and dad?

My parents have been fighting a lot. My mom gets REALLY upset and even throws stuff around. She even tried to get therapy and gave up on that. She freaks out over everything, and is always yelling at my dad. I heard her say she wants to send my older sister to boarding school. She also says she is going to “take off”
My dad handles everything as best he can. Never once has he hit or yelled at me. But now I just don’t know how to feel. Sometimes I hear them talk and it really hurts me. Should I do nothing like I always do or should I try talking to someone?