Then of course there are the financial consequences of a PWD requiring a substantial amount of care, which an invisible may be keen to avoid, sometimes by denying that care is needed and sometimes by expecting or even demanding that someone else provide care for free, regardless of the effect on that person's own health, wellbeing and finances.
This was very true in dads case, my brother couldn't mention the word 'dad' without mentioning the word 'money' in the same breath. He behaved much the same when mum was ill and she did not have dementia. Dad looked after mum and probably did far more than any of us realised but we all knew that she was very ill. My brother rarely visited them and it was only for 10 minutes if he did because he was very busy, he also lived a 5 minute walk from them. I visited mum and dad probably 4 or 5 times a week, I always did from the day I left home, they were wonderful parents, loving and giving and good company so why wouldn't I
My SIL has been a big problem over the years. She craves attention all the time and must be adored by my brother and their children. Even the dog has to idolise her and of course it does because she takes it to bed with her and she has it on her lap at the dinner table and feeds it off her plate which I find very strange and a little embarrassing. Her children are grown up and they laugh about her but my brother has always done everything to please her and still does. She gave birth to their children and is practically a goddess deserving much praise and unwavering attention as far as he is concerned and nothing or nobody else matters.
After they got married they actually sat my mum down and they told her that from now on nothing else mattered to him apart from his family which quite upset my mum. I was livid when mum told me but had to keep quiet for the sake of keeping the peace. He meant it and he has kept to it. We have cousins and a couple of elderly aunts but he has never had any contact with any of them apart a couple of minutes at the occasional funeral, then it is 'hello' and then 'goodbye'
It's not normal as far as I am concerned and I could go on and on about it all day but that is why he is how he is and I think he has had a lot to put up with over the years, I almost feel sorry for him because he has actually missed out on a lot. The last time I saw him was a year ago when I gave him the last cheque from dad's estate.