I've replied with links to evidence for why your statement that 30 is middle aged is wrong which you appear to have ignored as you continue to double down.
In my family, the majority of my granparents and greatgrandparents have died in their 90s. But I would never conflate that with national or societal norms. So let's look at the stats for the UK for life expectancy from the highest to the lowest: 81 (men) or 85 (women) in London and 78 (men) or 82 (women) in the North East.
Mortality profile: statistical commentary May 2026 - GOV.UK
But as stated in my previous ignored posts, middle-aged doesn't mean the exact age your at when your equidistant from your birth and your death. My best mate died in her 30s, that doesn't mean she was middle-aged when we were teenagers.
It's just the period of life between childhood & young adulthood and older-age. This massively varies depending on culture and individual experience. One of my friends identifies as middle-aged but she lives like a granny, she'd never wear the same clothes I do or go to some of the events and holidays I enjoy. That's nothing to do with her age or the age of our children but our own personal life choices.
For the record: you are wrong. You're not open to learning from people explaining why your thinking is flawed. I believe that you're probably a rage baiting attention seeker at this point.
Also: your daughter is 22, she's not a baby. Perhaps she's looking for a more mature (BUT NOT MIDDLE-AGED!) partner because she can't rely on her parent to be mature to recognise when she's got something wrong.
p.s. you're wrong