Mewho, I will reiterate what I said. Her behavior sounds to be NOT normal, especially if it is of recent onset. She might be experiencing the beginnings of dementia and aneurological exam and general health exam are both crucial to early detection. My friend’s mom started to do things such as you are describing, became paranoid and secretive. She refused medical attention, and like you, her daughter didn;t know what to make of it, and couldn’t get her to go for a checkup. Eventually she was forced to go because she fell, so they did a neurop work up as part of her battery of tests, and it turned out she had advanced dementia. By that time, she had cut off all contact with people, and insisted her husband was not her husband.
There are many things that can trigger odd behavior, including emotional pain, but this sounds to me like something that needs to be addressed right now. Your husband should insist on taking her for a checkup. If she is resistant, he should remind her that he loves her, and he is concerned that she is not feeling well but not telling him. If she still objects he should play the guilt card that moms often use and say,” Do this for me, if you love me.”