Tourist areas are being over-run by people getting out of the cities and turning up in their towns and villages, buying scarce food and clogging up hospitals if they take ill. Many tourist areas are not geared up for large populations, and are reluctantly asking visitors to stay away.
I think you should be pleased that you are not adding to this problem, particularly given your age and state of health.
Should you feel hurt? That's not a question the rest of us can answer, other than to say whether we would be upset in the same situation. If you feel hurt, you feel hurt, and there is no right and wrong way to feel (only different ways of dealing with it).
For what it's worth, no, I don't think that I would expect my children to cancel something because I couldn't go, although I would be hurt if they didn't replace the trip with another, more suitable gift. I would be annoyed with them for not cancelling at a time like this, however, but that's a different thread, and I completely understand that we are not responsible for how our adult children behave.