A world with multiple generations sharing a home seems to have, for the most part, become a thing of the past, and not necessarily for the best in all cases.
My great grandparents, during the depression and WW II had their children and grandchildren coming and going from the farm for many years as jobs were lost, and sons went off to war leaving wives and babies to be cared for. I'm sure it wasn't always sunshine and roses, but everyone made it work. Then when my great grandmother was elderly and bed ridden, her kids and grandkids took turns having her stay in their homes for several months at a time, before moving on to the next.
Most families today don't do this. There is just a real loss of coming together and making things work. I suppose in the past there weren't many options for a lot of families, and today there are more safety nets (pensions, social security, welfare/governmental help, and people who have done better financially than those of a few decades ago).
My mom lives next door and I help out with whatever she needs, and if she would get along with my husband, I would take her in in a minute, but she really has expressed strongly that she never wants to live with one of her kids.
I understand the want of independence, and at this point, I'm hoping I don't ever have to live with my kid. But it would certainly be nice to know that your family is there for you should the time come you need them to be there.