Is it normal for 92 yr old MIL in AL to try to “keep up with the Jones’” to her own detriment? And so many other things!

Living in a communal setting like AL is very much like being back in high school with all of the same cliques and cattiness and social expectations; she's making friends and it's perfectly normal to be interested in the things they are interested in and to want to fit in as much as possible.
As for lowering the walker - it reminds me of the exasperated parent saying "if your friends jumped off a bridge would you do it too?"🤣

DIL
I think you have correctly identified yourself as burned out. Let’s face it, with you in that state, there is little MIL can do that you will approve of. It takes a while to recover. Big Hugs
Try some exercise or therapy or both. 🤗

Well, I guess you need to figure out where your boundaries are, and stick to them. It is maddening.

My Mom used a cane only because other people told her that at her age, she should be using a cane. 6 months later, serious fall and now she is using a walker. Instead, she wants a rollator (I called it "walker envy".) She won't listen to why she can't use a rollator. I finally got her one from Amazon so that I could return it. She figures out for herself that she doesn't have enough coordination or hand strength with the brakes. She tells me that I purposely got her a "junk" one. I didn't, but told her I'd find a "junk" one for her if she really wants one. 2 years later, she moves into MC. Within 6 months, she doesn't want to use the walker and wants to be wheeled around because a person gets more attention if they are in a wheelchair. Independence is no longer important. She's primarily lost the ability to walk and can barely stand, but she doesn't care.

I told her that the day it becomes too dangerous for me to transfer her in and out of the wheelchair is when all the outings will stop. She's tested me more than once by deciding to sit at at the wrong time of the transfer.

I don't take my Mom shopping. She and I just don't enjoy the experience together; we never have. If I need something, I invite her along. She's usually just enjoying the change of environment and watching people.

Yes, I would lower the limit on her cards. Someone will show her online shopping and there goes the money. In addition, with the cards, she is vulnerable for any number of credit card scams.

My Mom used to get out of the car when the car was still going. It was only when her memory degraded bad enough that she gave me the clue to why she was doing this....she no longer heard the engine, so she assumed she could get out. Never mind that the car was rolling....sheesh. In the meantime, I put her in the back seat where she couldn't open the door from the inside. During that time, I also found out that she was not charging the batteries properly for her hearing aid, therefore, the batteries had a severely shortened life, like less than an hour, however, she didn't know the hearing aid was not working.

If only relatively recently your MIL has become negative and argumentative, check her hearing. She could be guessing at what you are saying and guessing incorrectly.

Figure out where your boundaries are. You feel the stress more than she does. Leave your strength for the decisions that are life threatening. Make sure that your actions correspond to the decisions. Consistency is your friend.

Yes it's normal. I suggest you allow the woman to buy all the clothing she'd like, which means she'll be super happy prancing around with her new friends. She's not living with you any longer. Allow her to enjoy her new life where she's at. My mother fell 95x in AL and MC for not using her walker, then forgetting she couldn't walk after the dementia got bad. She lived to 95. You can't force mil to use her walker, either, so put it all out of your mind.

A good friend told me you are only obligated to give them what they need. If you want to give them what they want that’s a bonus for them. I’m currently not taking my FIL out to restaurants because he’s refusing to shower. If you MIL is not behaving , you don’t take her shopping . You can bring her what she needs . They are like children . You don’t take a child who misbehaves to the toy store . So your MIL doesn’t go shopping for clothes etc. You still are not obligated even if she behaves , You have her placed where she belongs . Bring her what she needs . Don’t let her manipulate you .

Your MIL it sounds, is suffering from dementia.
Argument will do nothing. "She argues with everything" you say; yet you cannot argue with the wall; it takes two to argue.
She is now in placement and it sounds she is enjoying her newfound friends. To me this sounds like things are looking up.
I think that you need to cut your visits down a whole lot now; this has become habitual for you, and you need to embrace having more time for yourself. That may be harder to do than you suppose. You have acknowledged you need to disconnect. If you need help with what you already know is right to do, do seek counseling for a couple of sessions with a licensed social worker in private practice at counseling. They are often great at life transitions work.

If Dementia is involved, your going to have to let a lot of what she says go. You spent 2 hrs with her! I loved my Mom and we were close but I never spent more than an hour with her. Sometimes a half hour. But I went everyday because I lived only 5 min away. Was more like a check in. Your not the one who should be visiting or doing things for her, your husband should. My husband did not visit my Mom with me and I did not expect him to. If the tables were turned, DH would be doing most of the visiting with his Mom. I may go occasionally, but it would not have been a regular thing. She was not one of my favorite people. Its your husbands Mother, not yours.

If Mom has Dementia, there is no need for her to have her debit card, check book or credit cards. No matter how nice a place is, not everyone working there is honest. Too many people go in and out of your MILs room. There is no need for her to have any money on her either.

The walker. Slouching over is a no no. Those walkers are suppose to be set at a comfortable level so there is no slouching. People use walkers and canes wrong. You are not suppose to push them along with the person on the outside. You are suppose to push them ahead a little and walk into the frame. Rollators are a little different but still should be at a height you don't hunch.

I looked at your previous posts, and your mother is finally in AL after two years of living with you. 🎉

Make H take her shopping -- he has a lot to make up for what he made you put up with for two years. Don't make her your responsibility.

Let her be. Who is she hurting? Her brain is broken and will never get better, only worse, so you have to learn to pick your battles. And what you've listed aren't battles worth fighting, because YOU will never win and it's only causing you more stress not her.
Perhaps it's you that needs to educate yourself more on the disease of dementia, so you will be better prepared for what lies ahead. Like I said earlier, it's not ever going to get any better, only worse, so the better prepared you are for the changes the less stressful it will be for all involved.
Teepa Snow has some great videos on YouTube, along with some books she's written and the book The 36 Hour Day is also a great place to start.
And if it's so stressful to spend time with her, perhaps it's best that you only visit her once a week or every other week.