It sucks, but there is not much you can do to help someone who does not want to be helped. It's possible that by talking to him every day, you are actually helping him postpone seeking professional help. It's probably not healthy for your own sanity.

I have struggled with this issue. It is very hard to watch someone engage in self destructive behaviors without being able to convince them to stop. At a certain point, I find myself stepping away. It feels really horrible to do that, but what else can you do?

In many cases, my friends have eventually sought treatment and we have been able to reconnect. I hope things work out with your friend.