My dear...this sounds like it is just too much for you to handle, anyone to handle. Is there a Social Services in your local government that can come by for an evaluation? I mean, psychological/Alzheimers type behavior? This man has so many issues, some of which may be legitimate, others an attempt for attention. I wouldn't tell him someone was coming...let a professional see some of his behavior.
Even 911 when he is out of control...this situation cannot continue. Leaving the stove on, etc.--this is beyond normal and needs attention from professionals--not medical doctors apparently but mental health professionals. Go to counseling by yourself--there's a place you may find suggestions for governmental help for both of you. Just make an appointment probably in your car when you are alone...your doctor may have a list of professionals. Just do it--for yourself. When you say, "wits end" that means your own cognitive abilities are compromised and you need help from others--professionals that is.
I don't remember about your age, Medicare, etc. Medicare does pay for counseling; not all counselors take it though. A lawyer is an idea too--again, by yourself. They know where help is available and what your options are. I hope you have some financial control; if not, start working on it. If he is " a danger to himself and others" there should be help available to you. I know we all care about you and wish for a better life for you.