I am reading *Sadie* by Courtney Summers. There is this sentence that I do not understand. 

> 
> I want to live my life on the internet. Everything is perfect there. I found Kendall Baker on a computer in a library in some forgettable town along the way. She's beautiful. A girl with a glow. Eighteen years old, but the kind of eighteen they write about in books. The kind of eighteen that lives faster than the [**speed of hurt**](https://books.google.co.in/books?id=OntJDwAAQBAJ&pg=PT66&lpg=PT66&dq=lives%20faster%20than%20the%20speed%20of%20hurt%20sadie&source=bl&ots=h7GPXuz_nr&sig=ACfU3U1NJnRsgwx_am066y0goUagrTZbMg&hl=en&sa=X&ved=2ahUKEwiAqO6ovpLgAhUFWysKHRf9CqcQ6AEwBnoECAkQAQ#v=onepage&q=lives%20faster%20than%20the%20speed%20of%20hurt%20sadie&f=false). 
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What does the author mean by ***speed of hurt*** here?