I agree that there is little liklihood that you can change his attitude to money, but I do think you need to try to discuss it with him.
You say, he has always been a bit like this, but that it is getting worse.
This rang a bell with me, as that is precisely what my grandparents were like. In old age, although they had enough money to live on, they, and especially my grandmother, after grandpa's death became increasingly convinced that they DID NOT have enough to live on. It got to the stage where Grannie was living in a totally unheated house in December when we visited. She was in no way senile, but convinced that she had to save money!
So try to get your husband to see that now that he has retired you should be able to do some of the things that were not possible while you worked.
As for some years yet, you do not have your pension, you and he are living on his, and savings, I assume, but point out that you do have your pension to look forward to, so there is no reason to be so "careful with money" (parsimonious!) as he is being.
Tell him that you had looked forward to being able to go out sometimes, and the life of a hermit is not for you, however much he enjoys it.
Try to come to some agreement as to how your living expenses are used, and how much they amount to. And that there has to be some pleasures.