No spokes in the dumpster?
You rode 500 miles on a wheel-ful of overstressed and probably badly-tensioned spokes, and if only one more broke you are lucky. If you had bought a couple spokes (repairs and spares) and fixed the wheel, you wouldn't have two broken spokes.
As for your earlier experiences .... how many spokes? How strong a rim? How hard did you ride it? Without knowing every detail your prior experience is meaningless.
What is slightly less meaningless is that you ignored a broken spoke for so long .... and seem shocked that all the parts on the bike are important to the bike's overall function---particularly when riding shirtless at 35 mph with the fast guys .....
So .... why not go to the dumpsters and get a bunch of junk bikes and build a couple of back-up frankenbikes just to tide you over .... or just collect whichever wheel you need from junk bikes until you get a couple good ones.
When I absolutely needed a bike every day, I usually had two or three ready and a few more nearly ready .... just from pulling stuff out of junk heaps and collecting discarded bikes left out for the trash collector. Can't miss much work because the bike broke ... bosses tend not to care why you weren't there, and tend not to want to you back.
Whatever. It is hard to tell what to take seriously on BF, so my default is "nothing."