I have shared it!
Thanks to my husband's counsel (he retired many years before I did), I was able to do the right thing from the get-go: get the REAL Medicare with a Medigap Plan through his private company's insurance.
In fact, he had some problems at first because he hadn't signed up for Medicare when he was 65. He retired at age 62+ and wasn't eligible for Medicare at the time. We then moved abroad for my work. When he turned 65, we were both residing outside the USA and he was covered through my international organizations' insurance plans, so there was no immediate need for Medicare.
When he re-established residence in the USA (he decided NOT to exercise the option to reside abroad, as I chose to), we had to prove that he had been covered by health insurance from the time he was 65 years old until the time he chose to enroll in Medicare.
Obviously, we were able to do so. But he informed himself about all the complexities of Medicare and I have been the beneficiary. Although Medicare does not cover my health costs where I reside, I have separate coverage for that - just the most basic plan, but it works without a hitch.
Unfortunately, I was not able to use either of my IOs' plans because they had two different insurance plans and I had not met the 10-year vesting period for either when I retired. But when I became eligible for Medicare, I began paying the premiums for Parts A & B from my Social Security, and have had no problems whatsoever with using it when I am in the USA.
I am SO happy that we were able to arrange all of this BEFORE either Trump Reign of Incompetence and Terror. It was complex enough then. But there were competent people in both Social Security and Medicare in those days.
Eta: I have NO plans EVER to return to full-time US residence - especially not now - but if need be for whatever reason, I have the bases covered as well as they can be ... unless ...!
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