As a driver of 25 years and a cyclist of a few more, I've realised we just have to accept what's happening.
The behaviour of other road users is something that can infuriate us all. I see so much on a daily basis from all types of road user that seems arrogant and selfish. I see things that are foolish and I see mistakes or errors in judgement that all us make without even realising.
The trick for me, is to decide whether I'm actually affected by what has just happened. Is it worth getting annoyed over? Did anyone get hurt?
Best thing to do is let it slide, or you'll be cycling or driving on edge most of the time, waiting to explode on the next person who forgets to indicate when turning into their drive.
Every group of road user has their own difficulties to live with from other road users. Like it or not, we are all entitled to be there and we all pay taxes that contribute to the roads. A little patience goes a long way, because one things for sure, it's only going to get worse for all of us.