I want to help him

Before I was in love with one classmate and we were really good friends.Then he rejected me and we didnt communicate for like more than an year but now we are friends again. The problem is that he is in a really bad mental state. Beofre several months he lost his mum, before that he got rejected and just the pressure on him is big.I understand that his life sucks a lot but I really want to help him because I love him. I see how he trusts me and thanks me that I am by his side but in the same time I feel like I am useless. Before we chatted about funny things and it was a pleausure to speak with him but now he is so cold.

Everytime we chat he only speaks about his awful life and how he wanna succeed and about loneliness and sadness.He has nightmares about his close ones dying. Obviously I am telling him that I am here,that he has friends and can count on me always but it's like our friendship is much different than before. It's hard for me to undrstand is it because he is somehow scared that I may fall in love with him again or he is just cold because his life made him in this way.He said that he is sorry for what he has done to me and that he feels like the desitny is revenging him for eveyrhting bad he has done but believe me...he hasn't done anything bad at all..He doesn't want to go out.He is literally only studying and sleeping. I am trying to send him funny pics or talk about something else but it's never working.I am in love with him again but also I understand that probably it's impossible to win him.Even if I don't share my love with him, I want at least to help him. We have like future plans to be friends after school (we are graduading soon) and that if one of us needs advice or money or whatever, the other gonna help him but now, I am so worried about him.

Hey,
first off: I'm sorry that you have to go through this! You're a really good friend for trying to help him.
Have you talked to his family members/ close ones about his tough situation? Because this doesn't sound like something that'll just go away soon, this sounds like serious mental issues. I think that he needs professional help. Now you obviously can't arrange that on your own so I'd suggest talking to one of his family members/ close ones. They must be worried about him, too.