Don't get bummed out we've all had bad riding days like that but there really are very nice people out there that yield the road it's the 1% that give us the bad taste in our mouths. I find that if you ride with authority the cars respect you more. That will happen when you put in the miles and learn some of the road riding basics. I always watch myself at intersections and where cars are parked along the side of the road.
And if I'm in a turn lane I take up the whole lane. You might want to invest in a mirror that way you can see what's creeping up behind you.