I have to help a good friend, Help?

One of my good friend's mom died two years ago.. And I dont think he got proper help from it. He just got dumped by all his friends. I've tried talking to him, but he like, just wont talk or anything he'll nod his head, or cry. At our farewell he was like crazy crying and stuff and I'm really unsure about this. I know it's like none of my business but I have to help. The only problem is that I'm friends with him and also the group who dumped him. I don't think they like that I'm helping him, they kind of hate him. So basically what do I do? I want to help him without getting him mad at me.. I dont really want revenge.. Just some words or some suggestions about what to do. He's seen multiple people about this and I don't know if there is any hope. He feels suicidal.