Suggest Ways To Deal With Person Suffering With Fibromyalga

I have a sibling that has been diagnosed with Fibromyalga, but he also has been incredibly reliant on his parents for most years of his life. Our Dad passed on three years ago, Mom has been moved over to an assisted living place doing well since September. Brother is doing odd things like taking her back to her house over night and then bringing her back to assisted living the next day (she has dementia, basically putting her into a mixed up mode for a day or so after), we can't get him on board with her situation. He is virtually impossible to talk with and he drinks beer daily, hopefully keeping up with his Fibromyagla meds even so. We are trying to figure out how to handle our brother as we think he is unstable. This is such a short piece on what we're dealing with..while trying to have the best interest of Mom at hand. We hope he is thinking clearly, but our Mom is almost the only female he chooses to have any patience/regard for. He needs counseling or something seriously like -- now, and we would have an impossible time suggesting that.