"instead of doing anything serious about it, we've done almost the worst possible option: require every one of us to be a customer of these monstrous companies, with little regulation on cost or other government oversight"
This is a common misunderstanding of the economics of this situation. The principle involved here is "Adverse Selection".
To illustrate, let's look at automobile liability insurance. The reason this insurance is so affordable for most americans is that 1) everyone with a car must pay it and 2) there is price competition among insurers.
Imagine for a moment that automobile liability insurance was optional. Who would benefit the most from having this insurance? Accident-prone drivers or non-accident-prone drivers?
That's right - the accident-prone drivers.
And since accident-prone drivers have the most incentive to have liability insurance, you would see the customer pool of the insurance start skewing heavily towards these high-risk drivers.
Then, since it's mostly the high-risk drivers in the customer pool, the number of claim payouts would go dramatically up along with the average payout per claim.
In order for the insurance company to remain in business they would be forced to raise their rates OR to be super strict about not insuring customers that seem risky.
Naturally, the insurance business only works if you have more money coming in than going out. And in order for the insurance to be "affordable" to most people, then the risk needs to be spread amongst most people (not just the more risky ones).
So, while I understand and share your frustration at the current state of health care in the U.S. - it's important to point out "why" everyone needs to be insured in order for the rates to be "affordable".
Of course there are other important variables affecting health insurance premium rates (rising health care costs is a major one), but the "Adverse Selection" issue is probably the most important.
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Another point to consider is that the current big health insurance companies have focused their skill on just a couple things:
1. Avoiding risky customers (by denying them or offering only super-high premiums)
2. Paying out as little as possible (by reducing health care costs and denying claims)
The dynamics of the health insurance market are about to be dramatically changed. #1 will no longer be nearly as important and there will be a huge jump in the size of the market. This will be a huge opportunity for disruption in the industry.
The old health care companies are extremely slow, bloated, and resistant to change. It's easy to see that new entrants will be able to grab significant market share from them and initiate some real price competition.
It's frustrating to have to wait the few years until this happens, but I'm very optimistic about the future (assuming the recent health care reforms won't be diluted before they can be enacted).