My parents are fighting, how do I deal with it?

Mom and my Stepdad are mad each other all the time! My stepdad wont talk to mom unless she asks him a question and then he will grunt an answer or tell her to mind her own business or something like that. She tries but when he does that stuff it puts her in a bad mood. When my stepdad gets mad he yells at everyone and will be a jerk for several days at a time. They dont even hug or kiss or say "i love you" anymore. Its been like this for a few months now. My stepdad used to hit my siblings and I, and verbally abuse us but that stopped about 3 years ago. I can't just tell them how it makes me feel because he will get mad again. I'm 17 and their quarrel is stressing me out! I feel like I am constantly walkin on eggshells! I have prayed like crazy about it and my Pastor knows but it only gets worse. Please help me, how do I deal with it all?!?