"unfriending" people

I don't like unfriending people on Facebook. Until today, I have done it 2 times. First: someone I wasn't sure about accepting a friend request was posting bizarre and inappropriate things on my wall. I figured it was just easier to unfriend her. She was not happy about it, but in the end was unable to ackknowledge she had been inappropriate and told me she had "meant well." Well, I did not agree. Second time, I did it really impulsively, I was angry over something and unfriended them without thinking it through. I later apologized for my rash choice, which she graciously accepted.
Most of my "friends" on facebook have very different points of view than me. I don't always like things they "like" or agree with their posts, but I am sure they feel the same way from time to time about me. Occasionally, I will respond to some posts, but generally try and refrain, because what it the point? My disagreeing will not make them change their point of view, any more than their opinion will change mine. Agree to disagree, you know?
Well today I did unfriend someone. Not rashly. Not because I was angry. I think it was a long time coming. For several years now this individual has sent me emails, most of them political in nature. I have largely disagreed with most things they sent, and after sending me a pretty nasty email comparing liberals to people who are mindless drones, I asked them to stop sending me emails political in nature and only send emails with updates on family. Today though, I guess what "broke the camel's back" was a post on her wall that was incredibly patronizing and derided the poor. I had enough I guess. If it makes me intolerant, I will own that. I have a pretty good sense of humor, but cruelty at the expense of others is just not okay. I don't think I need to try and be friends with someone who has such a blantent disregard for other peop