I know I've done this sort of thing on another thread.. but hey.. it's part of what I do for a living.. so here goes.
Listen to the people who are advising you to seek some help from the Samaritans. They are a good place to start. You are supporting your friend, who's supporting you? Mudcat is cool, but we can already see that it is a forum in which stuff will be discussed, rather than in which you can be "listened" too. So get yourself some support as well.
I've also seen suicidal behaviour turn into chirpy behaviour. It isn't always a good sign (sometimes it's fine). Get some proffesional help. If people are offering it for free, grab it and use it. I'm sure you are aware that the Samaritans aren't Counsellors (note the capital "C"). However, they can be just the thing that starts a recovery off.
Good luck. Again, P.M. me if you think it might be useful.
Thinking of you.