I'm nearly as heavy as you Lummox, maybe more with my little dog on the back rack. Definitely more with a load of groceries.
I broke 2 or three rear spokes on my Mu XL when I got it a few years ago- despite some attention to tuning. After I took it to my LBS the second time to have it tuned they said "We're gonna fix this for you." When I picked it up I was shocked to see that they rebuilt the wheel with 12 gauge spokes. I had to buy a new spoke wrench- and it's not that easy to find a 12 gauge spoke wrench. I know there is some controversy about how much if any stronger thicker spokes are, but I gotta tell you that thing has not budged.

You might consider a bike with an internal gear hub, also, because the spokes will be shorter and the wheel that much stronger.
As with all folders be careful about applying force to the handlebar; the long stem is more easily damaged. Consider riding it as short as is comfortable. Also consider the fat-tire route to reduce applied dynamic forces to the frame.