Was going through exactly what you just described. She took him to a doctor.
The doctor told her to make sure he talks to five to seven people a day. Just communicate with five to seven different people each day. She said it turned him around.And was better than considering or taking him to a therapist.
She said he's developing relationships with different family members and friends from the phone, and from the porch. And he's enjoying his calls and figuring out who' he's going to call each day.