Nicole - as much as I sympathize with what you had to do to bring your H over here, you're still elevating those actions as 'special' sunk costs compared to them functioning as 'actual' sunk costs. You would not have had your marriage without it. Because it was an added layer of what you needed to do compared to someone who married someone else from the same country and didn't have to do that, you are investing more value in those costs than what they are - simply as a function to maintain your relationship and then get married. Please don't give them more weight than they deserve. This is a slippery slope as people can start making justifications for those sunk costs - i supported them through university until they got a degree and left; i was a stay at home parent and allowed them to advance in their career; and keep adding to that list.
Everyone can have a rationalization of why their sunk costs are 'special' compared to someone else. Don't do that and add to an already difficult situation.