How do main caregivers deal with extreme challenging behaviour?

My husband is in the so-called moderate stage of Alzheimer’s also vascular dementia. He can become very paranoid, not trusting anyone. He also gets very angry and verbally abusive. Which is very difficult to deal with. I’m also physically disabled which doesn’t help. His behaviour although I know he can’t help it is now affecting my health! He will not except any outside intervention, professional carers or attend any group sessions. He only wants me. Please if there is anyone else who has experienced this. How did you deal with this?