I've broken two helmets in two crashes. One where a lady unleashed her Chihuahua puppy at a MUP. I missed the puppy...I was knocked cold and the only bandage for my still badly scarred left shoulder was a sanitary napkin I found at the park's women's rest room. Not a scratch on the bike.
The second helmet died during a night time charity ride. My headlamp had some dark lines projected that hid a crack in the road and I rode right into it. Knocked out again, broken collar bone, chipped ankle bone, and bruised and cracked ribs. I had to pick up the bike and ride four miles to the finish area, put the bike into the truck (very ungracefully), drive home, and then bother my older daughter for a ride to the ER. Both front and rear fenders were jacked.
I'm a bit strict about my kid's and grandkid's use of helmets.
Brad