How do I get my 76-year-old-mom to stop complaining that her 79-year-+old husband is having sex with the maid?

Nearly two years ago now, the housekeeper team tried to change the amount on a check my mom wrote. They told my stepdad that her check bounced when in reality Bank of America called my mom and told her that the check had been manipulated. When my Mom told her husband that, he sided with the housekeeper. Since that time, my mom has accused my stepdad of "f*cking the housekeeper."

She is solely focused on anything and anywhere he is and believes that whenever he leaves the house that he’s meeting the housekeeper. She says he’s a pedophile because the housekeeper is as young as my niece. My Mom has since added on that he has a child with the housekeeper. We recently went on vacation, out of the country. My stepdad left us at the casino a little early to return to the unit, as soon as he left she started with the accusations again. This time he was leaving to text the housekeeper.

They have gone to counseling. My Mom left the counseling because the counselor didn’t agree with her. My Mom has traditionally been headstrong. When she thinks she’s right there’s no undoing that thinking. She is hyper focused on him. She’s also having short term memory issues. Her neurologist has recommended in home care and memory care but my Mom has refused it and blames everything she’s going through on my stepdad.

She doesn’t take her medication like she’s supposed to, so the neurologist didn’t think and medication for early onset dementia or Alzheimer’s would be beneficial. My Mom also has some hearing loss and needs hearing aids but doesn’t want them.

All of this has been more than a drain.

Both she and my stepdad have lost between 25 and 30 pounds.