I'm sorry to hear that your neice is so desperate so young in life especially. Please send her a card telling her that you care, aren't judging her, know family can be difficult, or whatever similar understanding statement you wish... so she knows you do care. Make sure they won't return your card first (for not being on contact listing.) If she is returned home quickly, don't let that stop you from making contact.

I suggest making this a therapy issue for yourself. When there is a family history of suicide, there is a tendancy for others to attempt, or at the very least be unable to cope well with life situations.