How do deal with liberal sibling that thinks they are right about every issue?

It happened again to me...a sibling that I don't live with THANK GOD came down on me last night spouting off crap about corporate America fleecing the working man and all the other liberal crap...I've been trying to hold my tongue but last night was the cake and I went off on them too.....I try to keep peace for my parents sake but I can't take it any more....Should I just write them out of my life once and for all?