One of the biggest flaws that I have seen with Steem so far is that they do not take into account abuse & bigotry. We should have the ability to block people if they are harassing us. It's the same big issues that FB and twitter deal with. I was also randomly downvoted but luckily they did not continue to do so. Really sorry this is happening to you, I only ever see you post educational, uplifting content. I don't understand why they would downvote you like that. :/