Welcome to Talking Point Jonshe, you will get support and understanding by the bucketload here, so sorry your wife has been diagnosed with dementia, there is lots of help on the medication side which may help her, we always (as people who care) feel out on a limb when the "D" word is mentioned, I know my dear dad found it so hard to accept, and before he passed away wanted to make sure my mum was OK, but she is still the same person only different and although hard, we need to try to get into their world, sadly also my mum in law has "joined" this exclusive club, and although you don't think you are doing it right, in truth you probably are
keeping a loved one safe and well is what you would do anyway, it just changes when dementia comes into play, do keep a diary on day to day changes, do keep your wife's GP informed, get anything you can in writing, especially if Social Services are involved as they have such heavy demands and none of us can remember what is what
if you do feel overwhelmed get, if only a day or so respite, just so you can clear your head, social services can arrange this, above all please take care of yourself, as you matter, keep posting on here whenever you need or indeed just want to chat, nothing on here shocks with everything going on in dementia world so someone will have had experience of the relevant concern you have.
Take care and best wishes- Chris