My MIL had a stroke about 4 years ago she recovered well physically & mentally. However over the last year or two I have noticed some odd behaviors I will list a few:
She has a thing for having a tissues in her hand all the time she will sit with it & twist it in her hands.
Many times she will be sitting by herself mumbling away & nodding away like shes talking to someone.
Biggest pet peeve she will clean kitchen counters with j cloth then wipe her mouth & arms down with it after been told many times that it is unhygienic & not to do it.
Many times she will sit on the toilet & not completely shut the door knowing there are other people walking around the house.
She does not always follow conversations will listen then ask a question which is completely off the topic. example We were talking about my neighbors daughter said she's 27 years old my MIL pointed at my 8 yr old daughter & said who she's 27 years old..gets confused trying to follow a conversation.
These are just a few examples she is on bp meds & diabetic med that's it nothing else.
Could this be a start of something?
As for leaving the bathroom door opened, my parents did the same thing. For them it was because it was just the two of them living in their house for decades, so why bother closing the door. Just an unusual habit. I close the door even if I am the only one at home !!
I doubt she's doing any of his " on purpose". Make a list of what you're seeing and get her seen.
I talk to myself. I've always done it silently but now that I'm alone in the house I often do it out loud. I don't talk to imaginary friends, though. If she is having delusions or hallucinating and thinks other people are there, that would be more cause for concern.
My mother (dementia) always had one or two tissues up her sleeve, and often one in her hand. Her nose dripped a lot, so this was just a practical action. Does your mom have a drippy nose by any chance?
Not closing the bathroom door is odd, but not necessarily a sign of mental illness.
Each of the items you mention by itself may not be significant. But all of them together should be discussed with a neurologist or geriatric psychiatrist.
What if you attached a packet of people wipes (like handi-wipe) to the J cloth container and explained and reminded her that the blue ones are for the counter and the white ones are for her face and hands?
How is her memory, by the way? How about her sleep habits -- have they changed significantly?
Don't write this off as "oh she's just getting older" to pacify relatives who refuse to face reality. MIL has a condition (albeit undiagnosed) that creates ongoing cognitive issues. Whatever it is will get worse, not better.
There are probably in-law bystanders (or hubby himself?) who have no problem with you running yourself ragged, if that's what it takes to support their head-in-the-sand narrative.
Your husband and his siblings would do well to get real, get together and make a plan for MIL's ongoing professional care. A plan that does not have you as the patsy.
Sorry if I sound harsh, but this forum is full of women who went down the rabbit hole of caring for elderly in-laws.
Your MIL is undeniably compromised; and getting worse. Of all the near and extended family, you are the one who is frustrated enough to reach out to this forum. Which tells me that you experience more of MIL's behavior than anyone else in her orbit.
Boundaries. Now! If MIL does not live in your home, keep it that way. If she is in your home, work on getting her out. MIL needs AL, or possibly skilled care.
Some meds make a person fidget more - it could be a reaction to one of her medications, even though she isn't on many. If generic drugs, the drugstore might be using a different supplier, hence an different medication that might cause side-effects.
Nutrition is also a biggie in dementia and 'odd behavior' in seniors.
RE: the bathroom door, she might be afraid of falling against the door when it is closed. She is a stroke patient. My DH fell against the bathroom door and now we leave it open all the time. We are grownups and we don't peek. Ray's visiting son was told that he can remove the doorstop but to please put it back after, and he just left the door open. (I had told him we are using the honor system and we don't peek in.)
Now I have a support bar screwed into the door itself so if the door is closed, the bar is useless.
RE: the counter towel - I have seen (and even done it myself) people wipe the dishes and then use the dishtowel to wipe their faces. I would say it is common and maybe she is a little confused. If the counter is clean (you said she does it all the time) - it is probably a pretty clean wipe anyway. Learn to pick your battles because reprimanding your MIL will not help her, and can make things worse.
BTW, how old is your MIL? Everything makes a difference.
My mom has the tissue fetish, does not close the door when she is using the restroom, and has full conversations with people who are not there. Not being able to follow a conversation was one of the first symptoms we noticed. She did not have these behaviors before dementia.
Get her evaluated and then you will know for sure. Unfortunately if it is dementia these behaviors will get worse. The tissue fidgeting - is the disease. My mom at times always fidgeted with her hands or the tissue etc. She also loved to clean or help with the evening dishes, but we realized she really wasn't cleaning properly. I had to hide the more toxic cleaning products and provide safer products for her to use. Eventually she was not able to differentiate what was a cleaning product and what wasn't. Maybe you can somehow distract her from cleaning or give her something else to do. My mom loved to sweep the floor or the driveway - it kept her occupied and she felt like she was helping out.