If you want to get really deep into it, I'd say it could be about a young girl suddenly taking interest in other people's romantic relationships now that she's had one of her own. She never noticed other people's romantic ordeals, but now she gets a little experience ("since she got that bicycle"), and suddenly she's much more observant of others with more experience ("cars") and their more complicated accidents.
I remember it was my older brother who told me:
"She didn't actually have a motorcrash."
If you want to get really deep into it, I'd say it could be about a young girl suddenly taking interest in other people's romantic relationships now that she's had one of her own. She never noticed other people's romantic ordeals, but now she gets a little experience ("since she got that bicycle"), and suddenly she's much more observant of others with more experience ("cars") and their more complicated accidents.
In this case, she might even be meddling a bit.