It’s tough. I lost a great deal of my sight last year. I had to stop driving, had to quit working in my chosen profession, and lost many of my hobbies (gaming, target shooting, astronomy). I went through a very difficult time myself. I realized that there is a grieving process similar to losing a loved one. Your friend ultimately needs to accept that his life is different now. Not ruined, just different. He may need counseling to help him cope with that fact. He is also cutting himself from myriad resources available to visually impaired individuals. There are tons of people who are living life to the fullest despite their vision loss and it might be healthy for him to meet and be mentored by some of these individuals.