That is, it didn't separate into two pieces that click back together, but actually broke? And there wasn't a stick or other debris in the spoke to make it break? That's not encouraging
Correct. When it breaks you need to replace it. Mine lasted about a year. I think I got a couple spares for $10. I still like the fenders and just bought another set for a different bike. I ride fairly fast over some rough pavement so it’s possible I’m tough on fenders. I switched to pdw after breaking a couple SKS longboards. Always seems to happen in the middle of winter.