@user1471462428
Yes, a BMI calculator would put him in the obese range but a friend of mine who's a doctor says there are a lot of other factors to take into account as well as BMI and that the calculator is far too happy to put people into that category. He tends to take around 5 points off it to give a more accurate picture coz various health conditions can contribute to someone's weight too. It might be an idea for him to see his GP and ask for a general checkup to see whether he does have any underlying issues.
Maybe I was a little hasty to jump on you, especially as you've now explained a little about his activity levels.
Regarding his lack of knowledge around household appliances, I know it's a real pain in the ass but next time you're about to fill the washing machine or dishwasher, why not call him into the room, you could try a really OTT excited voice or go to the other extreme and let out a scream, anything that you think might make him do his version of running to find out what's happening, then tell him you're going to teach him how to use each machine because you're thinking about going on strike, having a holiday (without him) etc, and he's going to have to do the washing, vacuuming etc coz you don't want to have to do it all on your own any more, he now has to be a productive member of the household,
Filling the washing machine is a 2 minute job and there's absolutely no reason why, as an adult, he should be able to say he doesn't know how to do it, the simplest thing is to teach him how, whether he wants to or not. It'll take an extra minute or two coz you'll be explaining how it's done whilst you're 'supervising' him actually picking stuff up and putting it in the washer. You can make whatever threats you feel necessary, say that you won't be doing his washing anymore, you'll be withholding sexy time or even say that you're going to stay with your mum/friend/anyone and you won't be back until he's pulling his weight around the house etc. If he spends all his time in one specific room, I'd say it's now his job to dust, polish, vacuum etc in there coz you're not going to do it any more. You could even draw up a rota and include the kids on it, even if they're only little they can help to sort out which clothes belong to who or do some dusting. If the kids are included in the rota, he might hopefully see it as though you're struggling to do everything on your own and just need a little help but you need to make sure to stick to your own bits of the rota and not do his, even if you see that he's left the washing up on the worktop, I guess you'll need to get a bit harder with him.
As I said in my previous post, I'm even heavier than your OH but I do have debilitating health conditions which contribute to my weight, BUT I now live on my own and HAVE TO do the washing etc. I may not relish doing these tasks and would rather be reading a good book but they have to be done.
Here's a thought, tell him that his weight shouldn't be a barrier to helping around the house, doing things with the kids etc coz you know a number of other people (I know from what I've actually read on the thread that there are at least a handful of us who've said we're in the same weight range) who are heavier than him, have underlying disabilities/health conditions to make their situations worse, who are still doing all the things he should be doing, so he had no genuine excuse not to be pulling his weight.
Unfortunately, not all children grow up with the luxury of two parents never mind two healthy ones, I know that only too well, I grew up u in a single parent household and my children grew up with my disability but were all well adjusted adults now and I don't think our pasts have been detrimental to us, if anything, in some ways is been helpful. I have 2 adult sons and (partly coz of my disability I needed a little help around the house) they both knew how to use all the appliances by the time they were 5 or 6 and were making hot drinks (all supervised of course) and helping to prepare dinner by the time they were 8. My younger boy has had a love of baking since he was about 8 and as he's got older, he's been creating allsorts of lovely things, yes, initially I did all the bits with the oven but he watched and learned and was dealing with it himself before he left primary school, I still watched him to make sure he was safe. He's now 26, lives almost 200 miles away and can operate all the appliances in his home. He still loves baking and did a degree in food which has given him the opportunity to work designing and creating celebration cakes for the company that supplies most of the supermarkets.
I know this bit about my kids has wandered a little off the original track but it was meant to highlight the fact that a chore (in this case cooking), once learned, can help you in your future life.
I'm sorry this post has been lengthy but there's just one more point to consider, do you still love him? I can see that you've said you've gone out of your way to try to help him but is that out of love or friendship? Finally, putting the children aside for 5 seconds, do you truly, deep down, want to walk away, if you didn't have children together, would you want to stay and love/help help him or not? Many people stay tigers 'for the kids' but eventually everyone is unhappy and the parents come to the realisation that the kids would be happier with 2 separate, happy parents than having them together and unhappy.