Read the first part of your question in which you talked about how your friend is wheelchair-bound after an accident in which his friend died. The best you can do is to stay in touch with him, send him things that he has always liked, and treat him with sensitivity but not as a sick or frail person. There are going to be plenty of people fussing over him, and it’s best you talk to him like a mature person capable of having mature conversations. I think the idea of him going to a psychiatrist is a wonderful one and one that you ought to bring up now and again. He is going through a mourning period at the moment, and while he will hopefully readjust to his new reality, you cannot cure what ails him. You can just help by being a good friend, which it sounds like you really are.