It's not too off topic @Cazzie. I asked you what does your DH do to manage stress over Xmas. From the sounds of it, it seems like he knows what he could do( 'man-tact') but there are barriers for him. Remember, that as a carer there is only so much you can do for him if he is not wanting to help himself.
When we care for someone, it's easy to feel stressed when they are stressed, but it's not possible to cure their stress. Like other illness, people need to do what they can to recover. It's not possbile to make someone else better - we can't eat healthy for them, or take medicine for them. We can certainly get them those things but in the end, it's up to them to take it. Remember there is only so much we can do. To @happygirl and @Alessandra1992 points we can't please everyone.
We have another 10 minutes to go before we finish so any please share any final thoughts on this topic? If I may, could I ask us to reflect on how we might get back to enjoying some aspect of Xmas?