I've never defriended anyone because we disagreed politically and you're quite dense if you really think that's why I defriended him. I defriended him because after years of defending him and being nice to him on and off this forum, he tried to attack me, unprovoked, in order to try to impress the same people I had defended him against.
The closest I've come to defriending someone over politics is when I defriended frogman. I didn't do it because I disagreed with him but because he became totally unhinged during the election. I had him muted from my feed for well over a year anyway because I found his posts kind of annoying.