Your boyfriend should be evaluated by both a therapist and a psychiatrist. The therapist might suggest therapy. The psychiatrist will most likely focus on medication. In most cases, both therapy and medication are integral parts of a comprehensive treatment approach to mental health problems. He should also have a medical evaluation to rule out a possible physiological problem.
If he agrees to therapy, it would be advantageous for both of you to meet with the therapist. Therapists often request at least one session with a client’s significant other, especially when there are problems in the relationship. The therapist may request to see each of you individually. He or she may want to see you together; it depends on the therapist.
If your boyfriend chooses not to seek treatment, then I would highly recommend that you see a therapist. A therapist could assist you in dealing with the anger you have toward your boyfriend. A therapist could also offer guidance about what your “limits” should be in the relationship. The therapist, based on a detailed description of his behavior, might also be able to determine if your boyfriend has a mental health disorder.
His behavior is unusual, and it is damaging the relationship. He should seek help immediately. If he is unwilling to seek help and his behavior does not change, you will need to decide whether you should or should not stay in the relationship. The “find help” tab can assist you in locating mental health professionals in your community. I wish you the best of luck.