Golly, I bet you flinched OP at the first response! Men, older men, can be impossible. I've been through it, threatened to leave, dragged him to counselling and it's taken 18 months for things to improve. The denial you describe is what is called avoiding, avoiders are difficult to live with, they destroy your own belief in yourself.
Being in pain can make anyone grumpy, you really need to find a way to get him to a GP or alternative health practitioner. Or, the latter being expensive and hard to explore, you could try over the counter arthritis remedies. There was a thread on here recently, people recommended Boswelia, I take turmeric, you could go to Holland and Baratt and ask.
You do sound down and frustrated. Can you take a break by yourself? See friends or family or just take a few days away to find some space? I've found counselling helpful but that can be expensive. You might explore that avenue through your GP. It's usually CBT but mental health provision is better than it was. I got online CBT relatively quickly and the counsellor was very good.
You really do have my sympathies. 'Till death us do part' is all very well but if you simply cannot stand the other and the way he behaves, what's the point of living in deep unhappiness and ending up with a serious illness yourself?
We are all different and have different pressures throughout life and some are more resilient than others or are just able to cut off. I think the latter is a sad response but it might work. Living in a culture different to the one you grew up in brings its own pressures. The UK is not a pleasant place to live in anymore for many, especially the sensitive. Take care of yourself first. 