SOLVED. Urban fantasy (I think) [s]

[Kailey]

I read a book my senior year in high school (I'm a freshman in college now) and I believe the book had been published recently (maybe a year or two before I read it; it was relatively knew). For the life of me I can't remember the name, though I do believe it was something hopeful, like Sanctuary or Redemption. I also can't remember the names of any of the characters. I believe the story would fit under urban fantasy or maybe paranormal.
The story is about a girl who loses her best friend when she commits suicide. As she is grieving for her friend, there is an accident and she too dies. The next part of the story takes place in the Underworld; there is a dark city for people who have committed suicide, and the world outside the city for those who deserve it. The protagonist enters the city to search for her friend and attempt to rescue her. Because she did not kill herself I think she can technically leave whenever she wants, but she refuses to leave her friend behind. The protagonist is also in foster care and pretty troubled. I hope that's enough information; it's all I can remember.
It's a little dark and the title contrasts with the story. If anyone has any idea what I'm talking about, please help.

[Jessica (Goldenfurpro)]

Is it Sanctum?

[Kailey]

OMG! Thank you, thank you, thank you!

[Jessica (Goldenfurpro)]

You're welcome XD

[Michele]

You might also like What Dreams May Come -- similar plot though with a married couple rather than friends.