Slightly different situation. My ex husband is 11 years older than me, he is 65. I have noticed him seeming to age far faster in recent months. He isn't in great health, prostate cancer diagnosed at 50 and managed since), but also seems exhausted , especially noticeable when he is driving. I think retirement will come as a relief next year.
Then a couple of weeks ago he was scratching his foot and suddenly blood was spurting everywhere, he was rushed to hospital. I think the change really happened when he got covid, he worked all through lockdown , as a funeral director, so not pleasant, but then caught it feb 2022, and was hospitalised. And although retirement for him will be welcome, his elderly mother requires more and more of his time and care, and gets upset when he plans a break away or to do something with our kids.
I think the age gap really highlights his aging to me as well, and I worry about being left alone as only parents, because although our kids are adults 1 has MH issues and 2 are autistic and require additional support.