Bailing out on the responsibilities of caregiving of the spouse, thus forcing the burden onto adult children whose careers are cut short or obliterated may be one common reason this occurs.
It’s my responsibility into the later and me assuming their responsibility in the former.
Unexpectedly becoming the sole caregiver of an aging parent seems different to me. I can imagine some resentment, especially if it’s unexpected _and_ one is already the caregiver for their own spouse, children, etc. It changes your life plans, adds additional daily stress in your life, and may also add financial stress.
Even if they don’t divorce and one dies it changes your life plans
The only thing different is the bummer of divorce and the emotional fallout from it
HN folks I assume are expected to handle these sorts of obligations more than average due to tech career incomes.