There are certain assumptions and presumptions you are making in what you have written gypsy.
For example, I am sure you have some figure in mind that you think it takes to live in the US in reasonable comfort. What is that number even if you don't have it? I ask because I am sure the number you think it is, is in fact higher than a number on which it is possible to live quite comfortably in the US.
I can tell you of a place in S. California where it is quite possible to buy a reasonably comfortable 2 bedroom home in a golf complex for under $25k US. On top of that you would need about $6k a year for fees and maybe another $4k a year in heating/cooling/electric/phone, etc. So $25k up front and $10k a year to keep the place.
But really, I don't think that is your major problem. There are a couple of things in what you have written that point to your reall basic issue. One you say you can't get the price you want for your farmhouse and two you talk about your antiques etc. What I'd say these things indicate to me is that your point #5 is in fact not true.
You may THINK you are up for a simpler life but in fact your actions do not bear out your words.
You could sell your farmhouse tomorrow if you priced it right. The market decides what it is worth, not what you want for it. You could downsize as I have indicated above and need an income of around $30k a year to continue living in the USA in a warm winter climate (summers are damn hot admittedly).
Now if the investments you have, the early pension you can get and the income of the capital remaining from the sale of your property after buying your new little place will earn even near $30k a year then you can retire in the USA right now. But I think it will not be in the manner to which you want to CONTINUE to be accustomed.
You are talking about hanging on to your property in the US while AT THE SAME TIME trying to manage to live somewhere warm for the winter. That isn't reducing and simplifying life gypsy. That's complicating life.