"....aren't things supposed to get better?", all i can remember, PLEASE HELP ME!!!

there's this song that my local radio station used to play, i only heard it maybe three or four times and never caught the name or artist. and my radio station has a rep for playing a lot of songs for a couple months and then they are NEVER to be heard of again and this was one of them. i like it so much that it's been stuck in my head for about 3 years, but i havn't heard it since. all i remember is...
"......aren't things supposed to get better?" something something something "write this letter". it's a girl singing that part of the song but i think there was a guy in the song too like rapping or something, it was like r n' b or something, i dunno how to describe it. i hope someone can help me....thanks so much

It kinda sounds like 'Where'd you go' by fort minor.

I'm not sure though.