SNefferdoodle, not your fault (though you may want to calibrate yourself to the front of your car). With the 2-second rule firmly in place, and globally ignored, it is a wonder that there aren't more accidents, especially with Automotive Cranial Rectumitis so rampant on the roads these days. One of the reasons why I swapped out the factory-supplied "excuse me" horn for something with a bit of pentetrating power.
As to learning where you are, relative to your front bumper, I reccomend that you practice pulling up to something soft and flexible (and not pedestrian) - stick a tall stick in the ground, and pull up to it until you think you will hit it, then get out (after putting it in park, preferably) and check your distance. A little practice, and you'll get a good feel for it.
Still doesn't excuse road-rage-inspiring lane changes, but I'm sure that someone will eventually post a mod on installing photon torpedoes eventually...