Her argument is that the insurance company then can raise the pr

Her argument is that the insurance company then can raise the premium without any worry because everybody has to buy insurance.

Everybody has to buy food, gas, car insurance, house insurance, etc. for decades or centuries. But those are still reasonably priced. My guess is that she probably never bought anything before. Or, she did not quite understand the supply-demand and assumes only the demand will increase.

She probably don't know that in many many states, car insurance in manditory and if you buy a house with mortgage, property insurance is manditory. Yet, in fact, the car insurance is not only reasonable, it is actually lower than before the mandate, precisely because everybody pays.