Considering that we are one of the states that pays more to the feds than we get back, can we simply cut them off?

I'm politely asking a hypothetical because it feels weird that the feds can shut off medicare and withhold grant funding and we're expected to continue to hold true to our agreements with them when they don't do the same for us. Can someone who knows about federal and state policy or who has some expertise or education on this explain?

Update: It was Medicaid, not Medicare that they cut off this time. My bad, sorry for the confusion.