Eggshells 43/m 41/f

I’ve been with my partner for a long time (decades). In the last few years especially life has gotten harder. He seems to have lost any ability to control his emotions and outbursts when he is frustrated by things. And the smallest things frustrate him. The kitchen being messy, the remote not working properly, the dog won’t quit licking him, etc. I find myself feeding off of his energy and getting angry at him for it and walking on eggshells. This is not how I want to live my life, I want to be with someone who can let these small things go and can try and seek the positive aspects of life. I talk to him about my feelings and sometimes he’ll acknowledge that he overreacted and sometimes he doesn’t see it that way and he thinks I don’t allow him to have feelings. With a lot of effort we can usually move past it and turn our day around but it’s an exhausting exercise and I just don’t know how much longer I can do it. I want to be around positivity. I love him and would never consider breaking it off over this, it’s not aggressive or dangerous by any means, just not the energy I want to live my life with. Any advice on how to help him turn his negativity around?