@EmotionalBlackmail
How long was it since the great aunt had worked herself?
I've found with my DM that, partly she's become considerably more selfish and insular as she's aged, because she's very focussed on her own aches and pains and what her neighbours are doing. She has no idea what I spend my time doing, what I do at work, what my commute is like etc, she just isn't interested. She does assume I have far more free time and flexibility than I do though!
And her working life was so different to mine now. She did things like shop for an elderly relative at lunchtime and drop it off. I often end up eating my lunch in a meeting! She was also offered far more flexibility at work to support elderly relatives - more annual leave, lots of flexibility around timekeeping, no work outside working hours, extraordinarily generous compassionate leave.
My experience is that they lose awareness of any bigger picture - the reality of childcare commitments, FT work, commuting, even the size of houses(!) - because they become so focussed on their own situation.
My great aunt didn't work. Don't think she had done for 20 years. Even then it was 5-8 hours a week in a small corner shop. (Her previous husband looked after her financially.) And yeah you're right - like your DM, she was very focussed on herself and her life, and never gave a thought to how busy other peoples lives were.
I was surprised at the Staff Nurse though. Just assuming a busy young 30-something mother with 2 little primary aged children (and senior aged parents herself,) and also a part time JOB, would take on the care of an elderly woman who had just had a major op.