I have only "unfriended" people whose political rhetoric or personal opinions are extremely upsetting to me & against what I believe in. I unfriended someone & was able to Friend them back as long as we didn't discuss that subject anymore. She knows where I stand on it; and, the same goes concerning her with me. However, someone else in the same conversation was extremely insulting to me; accusing me of believing things I didn't; and, wrongly stating my motives. She was someone I knew from high school; but, I could no longer take it because she totally was misinterpreting me & falsely accusing me of things. She stated that she knew a certain book well; which she did not, & was accusing me of not knowing what I was talking about. Only one person that I know "unfriended" me who was also on the other side of the political spectrum. He kept trying to pick a fight with me & also accused me of numerous things which I didn't do nor believe. I wanted to be friends; but he just wouldn't quit with the accusations. When he realized that there was nothing valid to what he accused me of, & he couldn't "catch" me on something in order to bad mouth me; he simply gave up & said that he was "unfriending" me. I still consider him my friend & I hope he realizes that we just don't agree on certain things. He was trying to bring out the "animosity" that I "had" toward him which simply didn't exist.
I Friend people who are Friends of my Friends & who are interested in the same things as me: jewelry designers; jewelry-making; rocks & minerals; gemstones; the international gem trade; rockhounds; mining companies; jewelry supply companies etc. I went from being totally involved with Politics on Twitter to mostly spending time on Facebook under these above interests; it's made my daily life a lot less stressful than it used to be!