How can I get mental health help for my reluctant, disabled husband?

Hi-I am desperate and at my wits' end with my husband. He is 50, I am 41, he has one daughter at home who is 15 (all our other children are grown and gone), and we have been married for almost 5 years. Two weeks before our first anniversary, he suffered a severe stroke, which robbed him of coherent speech (although I can make sense of what he says most of the time), use of his right hand (fortunately he is left-handed), and he has only partial use of his right leg. We live in a very rural area on the same property as his parents, who are both 70 years old but in good health. Since the stroke, my formerly strong, kind, level-headed and loving husband has turned into a mean, childish, thoughtless, and angry individual. He has kicked our dogs...screamed at his son, his younger daughter, my son, and me...he abuses alcohol at irregular intervals...he has stolen money from me, locked me out of the house, and ordered my son to pack up and leave our house (which resulted in both me and my son leaving; I stayed gone until my son was old enough to be on his own, then moved back home). When he is agitated, he also strikes out at me physically, like a small child having a tantrum. I have managed to get him to pay our basic bills, but he blows the rest of his money on silly, unnecessary items and them yells at me because I do not make enough money to cover all the household expenses (I work 50 hours a week and drive 100+ miles a day 6 days a week to do so, and I attend college full-time; I pay my own gas, my own car payment, my own cell phone bill, and foot all the expense for groceries, household, and personal items). Lately, he has taken to disconnecting our Internet line when he gets angry; when I explain to him that I attend classes online and that I cannot afford to mess up my college education, he tells me "I don't care". The last straw came yesterday, when his son called me to tell me that my stepdaughter was going to stay up at my in-laws' house for the night because while I was at work my husband got drunk and was brandishing a loaded pistol, threatening at the top of his lungs to shoot everyone who had ever done him wrong and them himself. My stepson went on to tell me that he had come to our house later after removing his sister from the situation, found my husband passed out, and removed the pistol to my in-laws' house. I spoke with my in-laws today and we all agreed that the pistol needs to stay at their house, we are all drained from dealing with my husband's irrational behavior, and that he needs to get help (which I have begged him to consider, but he absolutely refuses to even discuss). He is very upset at the loss of his gun, has threatened to report his son to the police for "stealing" it (even though, to protect my stepson, I told my husband that I had arranged the gun's removal), and has also stated that his son is no longer welcome in "his" house. My husband can say all the right things to a doctor and act perfectly normal in the doctor's office, but as I have told his PCP, his neurologist, and his therapy team, "you don't see him at home". We have tried several antidepressants, but they seem to make the problems worse. His mother has asked me to look into having him committed, as she feels that we all may be in danger from his irrational and aggressive behavior-especially me, as I am the one he takes his anger out on the most, and she has sworn to have him arrested if he creates one more incident. I have no idea what is involved in the process of "commission", but I am very willing to entertain the notion if it will get him the help he needs and give all of us-including my husband-some peace of mind. Can you offer me any advice? (PS-sorry for rambling!)