I think this song is about Sarah sympathizing with someone who has been broken and has trust issues, which she can feel their pain, which makes her want to get close to them, either as a friendship or maybe it's sort of an attraction for a relationship, but she doesn't know if they'll mistrust her and run away from her, so she isn't so sure if she can let them in. She isn't completely sure if she can handle the burden of dealing with their problems either.
In terms of what she actually is saying about the lost dog, it seems like it is someone who has been betrayed and mistreated by other people who they were supposed to find "home" with, so their friends and family. They then run from their problems and hide all the pain, thus the lines "home's not a word you say something made you stray off like a feather in the wind" and "why you burying bones out in the yard?"
I think this song is about Sarah sympathizing with someone who has been broken and has trust issues, which she can feel their pain, which makes her want to get close to them, either as a friendship or maybe it's sort of an attraction for a relationship, but she doesn't know if they'll mistrust her and run away from her, so she isn't so sure if she can let them in. She isn't completely sure if she can handle the burden of dealing with their problems either.
In terms of what she actually is saying about the lost dog, it seems like it is someone who has been betrayed and mistreated by other people who they were supposed to find "home" with, so their friends and family. They then run from their problems and hide all the pain, thus the lines "home's not a word you say something made you stray off like a feather in the wind" and "why you burying bones out in the yard?"