Depression and social anxiety are both possibilities, but without being able to interview him it’s difficult for me to know what is wrong. The fact that he doesn’t come out of his room might be a sign of social anxiety. He apparently doesn’t like interacting with people. There can be many reasons why, but clearly it makes him uncomfortable. As a result of his inability to interact with people, he seems lonely. Loneliness can cause depression. There could be other problems as well but again without more information, it’s difficult to offer anything beyond a generalized response.
If possible, encourage him to seek help from a mental health professional. These are treatable problems. Depression and anxiety are two of the most common psychological disorders. Effective and evidence-based treatments exist for both. If you suggest treatment and he refuses, realize that you’ve done all that you can. You can’t force an adult into treatment (except in very rare circumstances). Hopefully, he will understand that he can be helped and will decide to seek treatment. It certainly would change his life for the better. Please take care.
Dr. Kristina Randle