Cyclists can be an absolute nightmare too! Some will ride two or three abreast on the narrow lanes around here, not letting cars pass them. On numerous occasions I have seen cyclists jump the lights as if the rules of the road don't apply to them!
Sure there are plenty of dick-head cyclists, but a couple of things are worth noting.
First, cyclists acting in an irresponsible fashion are rarely a risk to anyone but themselves. Drivers are very rarely killed or injured in collisions with bikes - although cyclist often are, whether or not they are to blame. Acting irresponsibly when in control of a one ton car (or multi-ton lorry etc) is lethal to other road users. Being irresponsible when riding a few kg of bike is usually only a risk to you.
And a tiny minority of deaths and injuries caused on our roads and pavements involve collisions between pedestrians and cyclists - so in 2013 only about 1.5% of pedestrian deaths or serious injuries involved bikes - the rest motor vehicles.
And worth noting these stats don't tell us who was to blame, nor whether the accident was on the road or pavement. From my extensive experience as a cyclist and a pedestrian, cyclists are much more at risk of irresponsible behaviour by pedestrians than the other way around.
The other point worth noting is that as a cyclist you tend to be far more aware of what is going on around you and also better able to negotiate situations than you ever are as a pedestrian or motorist. So the cyclist you may consider to be being irresponsible may be very well aware of the situation around them and in complete control of negotiating the situation.
Not trying to defend all cyclists, but cyclists as a group often undeservedly get a very bad press, despite them being perhaps the most vulnerable of all road users. And often those who have a go at cyclists haven't been in the saddle for years, if ever. Before having a pop at cyclists I'd recommend spending a week cycling around London, or any other city, or just negotiating those country lanes you speak of. You might well change your tune, as I have know many times when friends of mine have taken up cycling.