Have visitors about to arrive, lots of posts that haven't read so apologise if I'm repeating other OPs.
But I need to log off soon & no time to scroll down through all the responses.
I'm of a similar age to you - I'm nearly 62, my DH is 9 years older,
The difference is that DH & me have been married since 1988.
I have noticed that my DH has problems with his balance - been getting <what he terms it as> 'wibbly wobbly' especially first thing in the morning or on hills & steep slopes.
When we went to Polperro to visit family who live there recently (if anyone knows Polperro in Cornwall, it's all very steep sloping streets!) DH was on his arse more than his feet. He got very cross with me trying to help him & told me to go on ahead to the hotel that we'd booked & he'd follow me. So I left him to get on with it. He arrived at our hotel with a huge bruise on his forehead & it seems someone had taken pity on him & given him a lift into town. I felt like shit leaving him, but he was insistent that I go on ahead & I had no choice other than to make a big scene.
This and some problems with his memory instigated an honest discussion between us. I'm a qualified counsellor & will not shy away from something that needs to be discussed.
We saw his GP.
Then an appointment with a nurse who took blood tests, did lying & then sitting blood pressure tests. Also did the usual tests for dementia - gave him an address to remember then asked the date, time etc & 'who is the Prime Minister?' questions. He came out as borderline because although he knew date & time, he couldn't remember some of the address & had no idea of who the Prime Minister was. But, frankly, I said that I don't blame him for not remembering the unmemorable Kier Starmer😂
But, as he didn't remember the address that he was given & some other things he's been referred to a Consultant at local hospital for more tests & (hopefully)
a diagnosis.
The reason I'm telling you this is I feel it's better to know the what you're dealing with than not.
If your DP has suddenly changed in attitude towards you & become abusive, then, given his age, he needs to see his GP.