I am a cyclist and a motorist who lives in a bike-heavy area, and I can tell you this: when I am driving in my car, 99.9% of the problems I encounter on the road come from other cars. For every one cyclist that slowed me down temporarily, there must be 1000 cars that have done so. And I can't think of one instance where a cyclist endangered my life while I was driving...but I can think of many dangerous encounters with other cars. I'd venture to guess that my experience behind the wheel is typical. So why the disproportionate amount of hatred towards cyclists?

I believe it's a reflection of a basic herd mentality. Out on the roads, cyclists are targeted because they are different. Instead of driving a car like everybody else, they are riding a bike. That's being different. When you step out of line, that's when you get noticed. When you don't conform to established norms, some people really freak out. I've felt this to be the case for some time now, and it's supported by the reformed anti-cyclist on this very thread. Describing a cyclist on the road, he says:

This sort of thing doesn't end with cycling. You will experience all kinds of resistance when you decide to step away from societal norms. Most of the resistance will be subtle. Some will be forceful and even violent. You just have to rise above it and affirm your right to choose how you live your life.