It is simmering just below the surface, however, my mother wants to baby me and would prefer I was alone with her. My husband is well aware of her competitive spirit, he is right - she is wrong, however, I need to take care of the 'person' and can't compromise that with her right or wrong. I am in the middle - they even talk through me to each other sometimes. I had to ask her if she would come out of the bathroom for him. It's tense and tiring.
I know it's easier said than done but you are in the middle which, I think, is exactly where you don't want to be. Nor should you be. If having an adult conversation with your husband and your mother doesn't fix this then it's going to be up to you to create some boundaries. Tell your husband it's not ok when he does x, y, or z. Be specific! Tell your mom the same thing. Don't plead. You're laying down ground rules for your living situation and these rules should be respected and followed. As a last resort ignore the behavior from each of them. Don't validate it and don't react to it. The payoff for both your mom and your husband is your attention. Remove the payoff and the behavior isn't rewarded anymore.
Good luck, cmor1954! I think you can do this. You shouldn't have to live this way while caring for your mom.
It's just horrifying for the rest of us.