Best way to approach Traffic lights

There is a little bit of road on the way home from work that's a 50mph zone with a set of traffic lights at the very end of the road. I've been lucky so far that the lights have either been red when I've approached them, or green and I can go straight through. My main worry is if they change to amber/red and I can't brake quick enough and I go through the stop line. If this was to be the case, what would be the best way to approach this ; how can you tell whether to keep going or to brake?

I'm one of these drivers who tends to approach things with the worst case scenario in my mind which I really need to STOP doing!

Thanks :)