Your brother's behavior, marked by prolonged social withdrawal and severe irritability for years, seems to be consistent with chronic depression, social anxiety disorder, or mood dysregulation. A professional clinical assessment is highly recommended.

He would be needing an in person psychiatric consultation rather than asking in this forum multiple people who will all advise well, but with the above complaints it is best to consult directly and get assessed. Good luck

Hi, thanks for reaching out. Avoiding people, frequent anger and changes in the way someone communicates for 3–4 years shouldn’t simply be labelled as “bad behaviour”. Sometimes anger is just the visible layer; underneath there can be stress, anxiety, depression or unresolved emotional issues. Instead of repeatedly telling him to “behave properly”, try asking him what has been difficult for him lately. And yes, a psychological assessment would be helpful. Take therapy. You can connect with me on nine two six six seven two six zero six five.

"Hi there, I understand that seeking help can feel overwhelming, but you’ve already taken the first brave step. I can guide you with a clear treatment plan tailored just for you, so you can feel better and regain control over your life. You can reach me directly on WhatsApp for quick support on seven zero eight two zero two two zero six two."

Hi, will need further history regarding the same to advise appropriately. Consult online for treatment

Underlying Concerns The brother's behavior—characterized by a 3-to-4-year history of social withdrawal, intense irritability, and impolite communication—points toward potential mental health concerns. As noted by the clinical psychologist in the image, these chronic behavioral changes are consistent with conditions such as: Chronic depression Social anxiety disorder Mood dysregulation Recommended Next Steps Seek a Professional Assessment: It is highly recommended that the brother undergo a professional clinical evaluation by a psychologist or psychiatrist to get an accurate diagnosis and treatment plan. * **Avoid Confrontation:** When communicating with him, try to avoid reacting with anger. De-escalating tense moments and maintaining a calm demeanor can help prevent further withdrawal or outbursts. * **Consultation Options:** If seeking professional care, you can book an online or offline consultation with a clinical psychologist. I can help doing that