**gives you the best mom type hug she can**
Don't blame yourself honey. Feel sad at her passing, but don't let that turn into guilt for "not being there". I had a friend take her life and I felt bad for ages that I was not there for her. I felt that I hastened the problems she was having by letting her mother know what was going on (if you want the whole story, I'll PM it to you) and that by doing that I only worsened her mental state.
Then someone told me that it was her choice to do what she did, not mine and that I could not choose for her.
Does that make sense? I'm shit for explaining things.
Here is what I did after my friend died: I sent mom a note (I was very close with her as a kid and I called her mother "MOM" since she stepped in as one after my mom died) telling how much her daughter meant to me, funny memories and how sad I was and I know that her hurt must be worse. Then I called her on Mothers Day. Even though her daughter is dead, she is still a mother. Letting her know that there was someone else out there sharing her pain helped she said.
I'm not saying to do this. Mine is an extradionary case since I had a good relationship with her, but letting the family know you care, maybe by doing something in her memory or donating to a cause you think she might like, can help ease their pain and hopefully ease your as well.
Find someone you can talk to -- not IM, not post to, but talk face to face with. Having a shoulder to cry on does a world of good. If you are college/uni (I'm assuming you are since you mention Facebook) see if your school offers counceling. Talking to an impartial person is SO helpful. Grief issues are not something to take lightly.
Finally, the best piece of advice someone told me about death "The pain of losing someone never goes away. It just hurts less often over time"
Cry. Grieve. Give it time. and DO NOT blame yourself.
**gives you another hug**