Arghhh.. I wasnt expecting a response like that, were you??
He sounds defensive and threatened.. on the defensive, which is perhaps not surprising because you put it to him that you DONT think this can work.. yet he is stuck in this sitch with work. I dont like that he didnt offer to discuss it some more with you, but said he disagreed...but then he was probably panicking?...thats why he said "as an argument, you can be across the ocean and it still works" - but he is not being very realistic. Being across the ocean is hard, and it takes ALOT of effort and will on both sides and love to make that work and maybe it would be hard, or too hard, or lead to a sitch that you NOW find yourselves in. Now that you have already been through a year of S, thats not a good time to be separated by work !!! Things need to change, so he is not being realistic.
However, he says that he doesnt plan to keep working so hard and this particular hard time wont last...? So he is looking ahead? I think for him (like my ex who says work is MENTAL right now).. your H is being hit by the Uranus-Saturn thing across his Work-Home axis... just as me and you are being hit across our Self-Others (relationships) axis. It affects people in different ways, and seeing as he is crazy busy and its affecting his home life, I can see that that is how its manifesting for him right now (as it is for my ex, having to go work away on site and not be at home, because of work). So he cant help it !??
My advice? I have no idea !!! Keep an open mind and heart.. see how if unfolds and dont fight it. The universe is bigger and cleverer than both of us...