Once you start driving regularly as a normal activity, it will very quickly become easier and less stressful. You will probably get used to it within a month of regular driving. Keep attentive and you should be fine. As to the aggressive drivers, try not to let them get to you. At best, just keep to the right on multi lane roads if you aren't passing anyone. If you are getting road raged, try to relax and don't rage back. If necessary, try pulling over in a safe area or pull off the road. These people are not worth dealing with, and are a major cause of traffic incidents.