Can We Have Different Opinions Without Being Nasty?

So when did this happen? Last year, I quoted someone in a sermon (maybe Henry Ford?), not because I thought he was Buddha or Jesus or Yogananda, but because the thing he said was wise (even if it was the only wise thing he ever said). I was verbally assaulted by someone who really didn't like the person I quoted. That was the first time I noticed it. Another time I quoted Eleanor Roosevelt (whom I very much admire), and a right leaning person got very snarky...not about the quote, but about its source. Now, I often find that if I share (on FB or anywhere really) a quote by someone I may have disagreed with a lot, but who happened to say something at least once that I liked, people who share my dislike of the figure will use the quote as an opportunity to go on a rant about how evil the human is rather than simply agreeing or disagreeing with the thing said. 

I am a democratic socialist, a spiritual humanist, a pro-choice, pro-peace, pro-marriage equality liberal. I'm a lefty, honest to Engels! And, I think Nixon and Reagan made many mistakes and that Bush II was utterly incompetant. HOWEVER, I can acknowledge that they were well educated public servants each of whom must have gotten something right a time or two. Is it possible that we can disagree with people's ideologies without assuming that they are evil to the core with no redemptive qualities whatsoever? Can a person be wrong (in our opinion) 95% of the time and still get credit for the 5% they get right????