Hello HollywoodBard: I don't know as I have the answers you seek. But I noticed this is your first post here on PC. So I wanted to at least welcome you to Psych Central.

I do think, years ago at least, there was something of an assumption that adult children would take care of aging relatives. (I presume this assumption still exists to some extent, but perhaps not to the degree it did years ago.)

You asked if there is a term in psychology for what happened to you. I don't really know of one. But then I'm not a mental health professional. So the fact I don't know of one doesn't mean there isn't one. Perhaps other PC members will have some suggestions.

In the meantime, here are links to 6 articles, from Psych Central's archives, that may perhaps offer some guidance:

How to Spot Manipulation

Manipulation: 15 Tactics A "User" Will Use To Control You

How to Cope With a Master Manipulator

Protecting Yourself from Manipulation

5 Manipulation Tactics Narcissistic Parents Use To Control Their Adult Children

https://blogs.psychcentral.com/recov...nd-demean-you/

I hope you find PC to be of benefit.