Yep, I think we all have had more than one experience like that.
) Riding east on a two lane highway with the sun almost down in the west at my back. A PT Cruiser was behind another car on a straight stretch heading west (seen them both), looked left into a field and then back. The PT Cruiser was in my lane passing the other car coming at me. I literally had 3 seconds to move to the other side of the fog line to keep from getting smashed like a bug @ 60 mph. I could have slapped her side mirrors when she went by... damn.
) Multiple encounters with deer. Sometimes they just don't stop, or they wait until the VERY last moment to bolt. Brake - Brake - Brake.
) Multiple encounters in town with cars and such cutting me off - texting or what ever...
) People turning left with no turn signal on when we bikers are passing. We have had a couple of people at work who fell into this one. Not good.
Staying alert at all times I think is key. Just like you did.