Some people just don't like you. Reasonably or unreasonably, no matter what you do, they will find fault with you. On the Internet, hate is easy to share - after all, as the saying goes, "On the Internet, no one knows you're a dog."
I've had more than my share of hate mongers. A few years ago, I was attacked by a rather distasteful blogger who accused me of running a scam business with my print-on-demand company. He got all his writer friends to post nasty things about me - even though he and I had not only never done business together, we'd never met. He happened to read an article I wrote on another blog - showing the growing trend of traditional publishers to tapping into bloggers. No amount of proof I presented would change his mind - I was a scam artist and anyone who worked with me was throwing their money away.