My friend told me he was mentally ill. He told me he was depressed and he didn't want to live. Then, he started to tell me he wanted to go to bed. Then he went off without a goodbye but he said goodnight to my other friend which made me think that I have done something. Then the few days, he started coming on and then off. He said he needed to see his psychologist. Now, all this has made me concerned. I sent him support messages but he doesn't respond. So, is there any point of trying? I don't know what I should do. I'll let him breathe but I am concerned about him. He hasn't been chatting to my friend either. I feel like I'm part of the problem. He told me he can stay in a mood for days. Isn't this a sign of bipolar? I really want to be there for people.