I took a 7-day cruise with my husband and kids as he was dealing with stage 4 cancer. It offered us a great opportunity to make memories as a family.
However our experience was very difficult in ways totally unrelated to the cruise itself. He began having very severe headaches that we later discovered were symptoms of metastases to the brain. As well meaning as the infirmary staff were, they were totally unequipped to deal with a medical situation that severe. The fact that we were visiting relatively undeveloped ports (Cozumel, Cayman) meant we couldn't address the issue until we returned to Miami. If I had to do it again, I'd request that he be airlifted back to the US from one of the ports. (You'll want excellent travel insurance to cover things like that airlift.)
The chances of that happening are slim. But I wish we'd had a memory-making vacation at a resort with better access to a health care center. It would have spared my husband days of terrible pain.
Sorry to be a downer. But it's worth weighing all the possibilities. I hope you have a wonderful vacation together wherever it is.