This brother is depressed, and the alcohol compounds that. He has an arsenal of guns and machettis in his room. He hasn't hunted in years. He is verbally abusive, threatening, and manipulative. My mother is 83 and deserves to have peace in her life, to be able to sleep at night without being woke up constantly, and told she can or cannot do things. She is still mentally agile and capable of making decisions. Her mobility is slightly impaired. she is an enabler and tolerates his behavior even though it is detrimental to her: lack of sleep, lied to, manipulated by this alcoholic son. He has lived there for 17 years or so. He has COPD and is on SSI. He uses oxygen tanks (but only at night). Since he has an income and ability to obtain further a
Your post prompts a number of practical concerns. Is your mother willing to move? Would she cooperate in having your brother forced out? You mention that she is an enabler. I have dealt with many situations like the one you describe. In most of them, the elder parent rants and raves about all of the horrible things they are forced to put up with. When it comes time to do something about it, they usually refuse, for various reasons. Your mother is familiar with the pattern of her life. Would she want to uproot that?
In spite of your brother's problems, he is a live-in caregiver that your mother may need or want. If he moved out, who would assume that role? Your mother also may get some peace knowing that, in spite of the problems, she is providing her son with a place to live and a roof over his head.
These situations are rarely as simple as they might seem on their face.
Having said this, if you believe that your mother is in physical danger, then you can contact the police and/or file a complaint with the court. There is likely to be a hearing, and if your mother agrees with you, then your brother could be evicted. You might also need to obtain a PPO against your brother so that he does not simply force his way back in.
Either way, you are going to need to agree on some follow-up plans for your mother. You should also discuss her estate planning with her to make sure that she has everything in order.