I am really sorry for all you are going thru.
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He is only 5 months old and this does happen when he thinks he is "King" of the house.
I would get him neutered, and try again with strict training. If you have no other choice, please contact a Reputable Yorkie Rescue. There are a good number of them in the NYC area.
Just don't bring him to the shelter, they will either PTS or adopt him out to someone not experienced and he will just keep getting passed around.
....I had a foster dog who was 7 yr, male, not neutered, passed around to 5 different homes, and he was abused. His behavior was the same as you explain. He finally got neutered and boy oh boy did he stop with that rage defense, plus he is finally learning to trust and the rules...
Best Wishes