Can anyone recommend an agency or person with experience in seeing the signs of emotional and verbal abuse by a person who is family?

Talk to the police as well. It's good to get things documented by the authorities. They will give good advice. Get yourself a good social worker to help you manage the situation and look out for YOU. Sociopaths are clever at manipulating others and if your mind does not naturally work thT way it will be difficult to stay a step ahead of their games. You need to protect yourself mentally and legally so keep good notes.

Contact Adult Protective Services part of Department of Health and Human Services to request an investigation.