Sorry, bit of a long one but this is what can happen when you promise never to put a parent in a home, regardless of the situation. A bit extreme but a true story.
Used to work with a woman, she was very smart, middle management and predicted to go far in the company. Bumped into her a while ago and didn't recognise her at first, she was scruffy and unkempt. She said let's go for a coffee and catch up so as I wasn't very busy that day I went.
It turned out that her mother started to get a bit forgetful in her early 60s to the extent that my colleague didn't feel she was coping at home, so moved her in with her family into quite a large house. The mother kept making her promise not to put her in care on almost a daily basis. Colleague's husband went along with it but said that if she ever got too bad the mother would have to go into care.
Long story short - kids were never able to have friends round because granny had a habit of walking into the room stark naked, sometimes covered in poo - they could never go on holiday as a family because Mum couldn't be left for more than a few hours - colleague had to leave work and they started having trouble keeping up the repayments on the house. After coming home from work to find that his MIL had left shit in the fridge the husband said he couldn't live like it any longer, they had no life, and either the Mum went into care or he was leaving. My colleague said she had promised her Mum not to do that, so he left. The lovely house was sold. The kids originally stayed with their mum but as granny's behaviour became increasingly irratic they left to live with their Dad. They felt that their Mum only considered granny in everything and didn't care about their welfare so they are now very low contact.
The mother is now dead but my former colleague was unable to get back to anywhere near her previous employment level and had a breakdown, so lost the house she bought after the split. She is now living in a crappy flat over a take-away, has lost her career, family and lovely home. She's a shadow of her former self.
As I said, an extreme example but some people on here have no idea what living with a person with dementia or complex needs is actually like and think that love can conquer all. My Dad had dementia and when he was able to I used to have him to stay. By the end of the two weeks I was exhausted (he only slept for a couple of hours at a time and would wander off at all hours). However much I loved him I knew I couldn't have him with me permanently. For his safety and my sanity he had to go into care.