No. Don't have the time or space, and ILs have plenty of money to afford whatever they want. (My parents are dead, but my answer would be the same). Also, they would just as soon eat a bullet than rely on any of their kids. They are of the mindset that assistance flows exactly one way in a parent-child relationship and would just as soon die as be a burden.
These were my parents. They were part of the "greatest generation" . . . born in the 1920's and Dad was a Marine in the Pacific during WW2. They did not have high incomes, but raised 7 children and saved enough money to take care of themselves until the end. Mom was in assisted living for about 8 months. Dad was in there for only one month (he was the toughest guy you can imagine) before he died. He never went to a nursing home, never took any pills . . . just died when his time came. He abhorred the thought of ANYONE taking care of him.
Like him, I have saved for my old age and never want to ask my only child to care for me. Visit me, yes. But I would prefer not to burden my child. I also agree with others on here who are talking about how long people live now as opposed to the past. My father's parents were dead before I was born. My father was astounded at how long he lived. Life was just a lot harder way back then. People got things and died. Now we live, but our quality of life is not always so good.
It's just hard to make these decisions. OP, do not feel guilty . . . those who judge are not in your shoes. Every situation is different.