What you are doing is very kind and noble. I really hope everything works out for him. I hope he gets the proper help soon, before he actually attempts it, or worse, he dies from it.
I'm sorry @ your friend. I, too, have lost close friends to suicide. Unfortunately my father also took his own life when I was 5, and my brother was 9. But I want to tell you a story, a brief one. My brother grew up w/ a guy named shannon. He was his best friend, and like a brother to both of us. He suffered depression ever since I can remember. We both always tried to talk him thru the bad times. We did everything we could think of. When my brother and shannon were seniors in h.S., (i was a lil' freshman.) shannon hit the lowest point i'd ever seen him at. He pulled up to our house one night (dropping my brother off.), and I knew he was real sad. My brother asked me to try to talk to him. I did, for 2 hours. I remember getting out of his camaro, and turning to look at him (i was crying.) I felt in my heart that, that was the last time I would ever see him again. I told my parents, my brother, anyone who would listen. Nobody took him seriously. I guess because he threatened it so many times before. Anyway, 2 weeks later, he blew his head off right in front of his already estranged mother (or deranged?) he said, "this is for you, mom." and he was gone. Just like that. That was 10 yrs. Ago, and although I don't blame myself, I still wish I would have done more. Anyway, I guess I just want you to keep trying, but please don't blame yourself if you can't reach him. When someone is suicidal, it is almost like they become that way because it seems to be the only choice they believe they have left. Good luck. You are both in my prayers.