I have about three I can list for this... and I'll be kind enough to give my reasons why!
First off is Blink 182's "Dammit". Not the entire song, but just the chorus. It's about how you need to be able to trust your friends rather than rely on doing everything just yourself; cuz when the time comes you finally give in and need help, your friends will more than likely not be there if you didn't want their help.
Then comes another Blink 182 song, "Stay Together For The Kids". It's from the viewpoint of little kids watching their parents argue and divorce, and how no kid should have to be torn between their parents.
Finally, "The Artist In The Ambulance" by Thrice. It's how one random act of kindness from a total stranger helped saved a man's life. I connect well with it, because I was in the same exact situation. :3
See, not just ONE song, but THREE!

*is an overachiever*
All the songs are on Youtube, I suggest checking them out. :3