Too tired to listen any more.  That has been my mantra these days.  My kids will not stop bickering.  I don't even ask anymore.  I just tell them both to shut up.   You would think that at this point, they would get along.  I deserve some peace before they move out.  At this rate, I will be packing both their bags and driving them to the bus station.  We can't get through a meal without some kind of argument occurring.  I have been cooking everything they hate lately, hoping that a common enemy (me) would unite them.  Sometimes when they argue and I know who is right, wrong, whatever, I tell them to shut up.  When they try to drag me into their petty issues, I just say I am too tired to listen.  I have even said I don't care.  I figure that just confirms their suspicion's any way.   I have been accused their whole lives of not caring.  Why are they surprised now?  It is amazing what happens to your parenting skills after 20 years.  When ever they use the old "you love her/him more than me" routine,  my new reply is your right.  Then I stomp away.  See how they like it.