Oh my God. As others have said - it's not your fault. Some people do get beyond despair and think killing themselves is the only way out of their misery, and they cannot be helped unless they want it.

Please please don't blame yourself for this. You have no control over this person, and were just trying to help. It's not a failure, it's a new beginning. Hopefully you can reconnect when that person is ready, and let her know you care and have been worried about her.

Now, it's time to take care of you.