My heart goes out to you as I think what will happen now is you will be in the situation of waiting for a crisis to happen, without any clue as to what the crisis will be and what the repercussions will be. Things will change but for now without help , you need to look at protecting both of you. For instance, take a cold and calculated look at your finances, how you can survive when the crisis comes as it no doubt will, how will care be financed as the way your wife is it will come to it. Take a look at your emotions that will also be running riot, try and forgive the other family or else the anger and unfairness of it all will eat away at you. If your wife is driving you demented then walk away for a while though I am sure you do this already.
I don't know your circumstances but if she is still deemed to have capacity (and sounds like she is after the SS visit) then now is the time to get power of attorney, wills, mortgage, house etc sorted. Look at carers allowance and attendance allowance if you haven't already got them. Look at how you can pay for help to keep your job going. It may sound ruthless but you have to keep the money coming in to survive thereby keeping options open for you both. It's a lot to think about and I know the situation keeps changing, emotions are raw and we just don't know what is coming next, and the person who used to be our ally and support now seems to be the enemy. Just spend a little time on these things as otherwise it will seem to enormous to even start. I always used the phrase "how do you eat an elephant" to keep me going, the answer being "bit by bit", and several years later I am still chewing.
You will need to probably pander to your wife's every whim to make sure you can get some of this in place, you may feel a bit of a traitor as there is an ulterior motive, but I have been in a similar situation, still am actually. In the long run to face and sort the mess is in both your interests, Try and get some lists done of what you now personally need to achieve and how it could be achieved, so you are prepared as best you can for whatever happens.
Your wife sounds like a wanderer and while she has capacity you can't stop her-use your imagination to think of different scenarios that may occur and how you could cope. No doubt whatever you imagine will not occur, something else you didn't think of will bite you on the bum! But at least you will have tried. Hide the passports, matches, lighters, power tools, keep a check on bank cards, cash withdrawals, keys, anything of value, paperwork, your work stuff-all are at risk. Keep up to date photo of her, warn the police, make sure the house has smoke detector, switch off anything you need to if you leave her on her own. You will never get to the end of the list and she will no doubt still "outwit" you but you need to think damage limitation.
Unfortunately your wife is in that terrible in between stage. They can still remember things and use things, find their way around, know date of birth etc and for that reason they are deemed to have capacity to make their own decisions. In one way you can understand the reluctance of those in authority as until there is proof that the person is a danger to themselves or others they are deemed to be able to make decisions for themselves, even if unwise decisions.
My mum was very clever passing MMSE's and still is clever/manipulative in some respects, but in the end she couldn't keep it up. Having to take her car from her "tipped" her over the edge, the crisis we were told would happen happened, and events took with her being sectioned. That was over two years ago and its still bad as really she wasn't ready to be "locked up", so I can understand why SS are so reluctant about human rights, but unfortunately our rights seem to be lost in all this, yet we have all the responsibility.
I am really sorry if this doesn't mAke sense as i haven't got the time(that is a problem for all of us i am sure) to make sure I get this right, and i sincerely hope I have not offended or scared anyone and caused further distress at the thought of where this might lead, but I wish I had been better informed when similar happened to me.
best wishes.
Sent from my iPad