Remind Me of a Novel in which...

[Rwconner]

... a couple is prevented from marrying because one partner has an obligation to take care of a physicallly helpless relative.

[Dreamwoven]

I am sure there must be at least one such novel but I have no idea which.

[Danik 2016]

+- Ethan Frome?

https://en.wikipedia.org/wiki/Ethan_Frome

[Dreamwoven]

You probably got that right, Danik: https://en.wikipedia.org/wiki/Ethan_Frome