It's really hard to take. There's almost no "there" there, and spending time with them isn't a fruitful endeavor, and even from a charitable "put in the time" perspective, they just kick into stories of regrets and mistakes and losses (real estate losses) and that doesn't seem to do them any good either.
My parents are immigrants, so I gave them decades of allowances for that, but.. man.. unsatisfying and painful the whole thing is.
I endeavor with all of my awareness not to be that to my son, ever.