It's another example of what I call the "shit oyster", taking a minor fact and building lies around it. In this case: the US gives Israel lots of money, Israel has money to spend on healthcare, therefore we must be paying for it. Somewhere in there there is a tiny bit of truth: money is...
...funigble (if given in cash, not tied to purchases from the US as most US aid actually is), and Israel is a relatively wealthy country. But it's really easy to take the fair question "why do we give non-defense aid to a rich country?" and twist it into anti-semitism, exactly what they're doing.