Driving Mystery

I drive 25 miles in one direction to get to work every morning. Almost the entire drive is on I90. Last winter the 10 miles of I 90 near my house went from smooth interstate to a lovely game of Dodge the Crater. Potholes big enough to seriously damage a car. The road shouldn't have fallen apart like that for a few more years if ever so PennDOT had to scramble to get funds to repair it. The repairs began on Monday this week and are currently on the Eastbound side only so I drive I90 to work and take local roads home. When they switch sides, I'll switch my pattern as well. So far this week the construction has caused a 10 mile back up a few times and I'd rather not be a part of it.
So, I was on the way home on Tuesday following 38th St to the Winter Green Gorge, a fun section of road with steep hills and sharp bends. From there to Station Rd to one other side street to get to Rte 20 that will take me home. Somewhere between 38th and Station I found myself behind a male drive that obviously had some issues. Ask my friends and they'll tell you I don't tailgate and am a far from aggressive driver. I've been known to get stuck in one lane on a multi-lane highway because I don't want to cut someone off to move over.
I had my blue tooth headset on and was discussing my day in general with Tara who was stuck in Baltimore, MD waiting to be loaded. I followed this gentleman down Station onto the other side street and was about 2 car lengths behind him when he suddenly slammed on his breaks and came to a complete stop. I stopped behind him in plenty of time and the person behind me got a little close to my fender for comfort. The man in front then stuck his left hand out the window and flipped the middle finger all the while staring out into his side mirror at me. I commented to Tara that this guy was acting strange and stated what he just did. I actually thought he was flipping off a house across the street!
He then punched the gas and tore off down the hill. I started up much more slowly however, the light was red at the bottom of the hill. A few hundred yards short of the light he slowed way down, I caught up and he proceeded to repeatedly slam on his breaks until he reached the light. He was then able to turn right on the red. I waited for the green light.
Now we are on a 4 lane road and sure enough he is moving very slowly up the road in the right lane. I stayed back for about a half mile and then decided to pass him. As soon as I sped up a bit and moved to the left, he swerved to the left. When I moved back to the right, he whipped in front of me again; each time slamming on the breaks.
At this point I was very concerned and just wanted to get away from this man so I pulled into a parking lot for a construction machinery company and counted to 100.
When I pulled out he was now 8 cars in front of me and after the next light, turned into a dirt driveway on the right. He had a companion in the passenger seat, arm hanging out of the car and seat tilted way back.
I honestly don't know what caused the burr under his saddle. Maybe he saw my lips moving and thought I was making nasty comments (those didn't start until after I got away from him). Maybe he was paranoid, maybe he thought I was someone else or that I was following him. Maybe 2 car lengths was too close for him. Then again, maybe he was drunk or just an asshole.
The unfortunate part of this is it keeps running through my head that he pulled into a driveway, which means he might live there, which means there is a good chance I'll see him again on the road. There is no other decent, timely way for me to get home so on the same route I will go but now I'm wary of the crazy aggressive driver that somehow picked me as a target for his anger.