I am confused at how you are struggling to get stuff done- like how you don't know if you can't walk into your own kitchen for hours? It sounds madness to me. I've got (well had, they are slightly older now, but not much) 2 under 2, and surely if you need to go into the kitchen you just pick up your child and go... If you need to make food, you put your child in the bouncer, or the sling (depending on what you're making), and just continue. You're in charge here. If you want to go into the kitchen to make food, then you do it...
Your older kids if school age shouldn't require constant supervision, should be able to clear up their own spills, do some tidying after themselves etc.
I still have no idea why you are doing 2 cooked meals a day - trust me, the rest of us are not we are eating sandwiches and beans on toast, even with tiny babies. Either you are quite inefficient at it (not surprising given you haven't been doing this juggling before, had meals cooked for you, had a cleaner etc) or your expectations are way way too high.
I think it's a shock to your system, but the juggle is a pretty normal thing even on regular times. I remember when my baby was about that age, mixing Yorkshire pudding, whilst breastfeeding in a sling, and doing a jigsaw with my not yet 2 year old, and thinking it's madness!! but it's what having multiple kids at home is like.
Your husband is clearly a sex pest, and I'd give serious consideration to leaving him. But the domestic stuff is pretty normal really. I don't think he needs to be doing more, as opposed to you working out what can be cut out, and becoming more used to the juggle.
It's been asked before but do you have a sling? It makes a massive difference to me in what I can get done with a velcro baby around.