First off you are right about the drivers. After moving here from Dallas Texas I was utterly shocked by the poor level of skill and judgment on general display. Both large metro areas, similar weather, similar roads, completely different drivers. I also understand the feelings when you first venture out on these roads on a bike, having been there 7 or 8 years ago. There are drivers who try to intimidate you with their vehicles - try to chase you off by literally threatening you with the vehicle. At least that's how you interpret it.
I'm not sure if the environment has improved since then, or I have - probably both - but I rarely get that any more. I believe that part of it is they are incited if they sense weakness. Wobbling, uncertainty, any overt display of fear. Part is also perception on my part, where a formerly fearsome close pass is now an irritant. That only comes with experience. You also learn to predict what they're going to do. That's second nature (or should be) when you're driving but they do react differently around bicycles and it takes time to learn to recognize and anticipate. These days I see more overly cautious driving around me than overly aggressive, not that I'd complain about that!
Another thing to keep in mind, even in dense high-traffic areas you tend to encounter the same people, over and over again. I don't like to be a training exercise for incompetent drivers, but the reality is unless there are a lot of cyclists riding solo on your roads you are training them just by being there. I think the key is to appear to be one more piece of traffic which is routinely noted and adjusted for, and to ride with that in mind. To not encourage bad behavior by becoming upset or acting fearfully. After a while, it just gets easier.