The lights were the headlights of a car from the opposite direction. The flashing was caused by the train passing between the two vehicles.
Same thing happened to me on the Blue Star Highway (You probably know it well) but it was not a train, it was two deers crossing right in front of me and the oncoming car. Hit the breaks as hard as I could, went from 80MPH down to about 50 in no time, just missed the second deer by about 6 feet.
Courtney is My Hero
If a man is to be obsessed by something, I suppose a boat is as good as anything, perhaps a bit better than most - E.B. White