Why don't you come back for a week yourself and DS, you need the break.
This move is not working out for you, you've only been there 6m, but I remember my first 6m where I was and, while much more isolated than you, no phones, no internet and no going out for months at a time.
I know what you mean by feeling a single parent, try adding in cutural bollocks habits and being told therefore that Men don't DO helping their wives raise DC etc...
I raised my son in spite of the presence of DH. 4ys on and I'm used to it, but I do get utterly worn down by it all and feel totally uninspired when it comes to things for us (DS and I) to do together. I'm working on that btw!
Could you have the option of living back home near friends etc? You could pop over to see him every few months and perhaps even take the DSS with you? See if you can make that work for you?
Men working away often have scant understanding of how utterly isolating and lonely life for an expat mum of a LO is. have no idea how to overcome that, and neither do any of my expat friends.
Friend of mine recently gave up on the living abroad thing, because of the schooling, it's a total shambles, and not even guaranteed for starting back in January...
My DH only realised when I'd returned back home almost broken, and suffering panic attacks at being outside. That, I think, is getting better, can't recall feeling too tetchy outdoors, but DS has just been indoors for over a week with Chicken Pox... LOL, my former life was good training for that!